Heavy rain in southern China have halted the search for victims and flight information black boxes that could tell why a China Eastern Airlines passenger plane plunged into a mountainside two days earlier with 132 people on board.

Rain water was filling the depression in the soft soil caused by the impact of the crash, state television reported, and the local weather bureau said there were risks of landslides, torrents and high winds as conditions deteriorated in the mountains of Guangxi region.

The wet weather was forecast to last for the rest of the week.

Flight MU5735 was en route from the southwestern city of Kunming, capital of Yunnan province, to Guangzhou in Guangdong province bordering Hong Kong, when the Boeing 737-800 jet suddenly plunged from cruising altitude at about the time when it would normally start to descend ahead of its landing.

The cause of the crash is yet to be determined, with aviation authorities warning that their investigation would be very difficult because of the severe damage to the aircraft.

Desperate relatives of people who had been on board visited the crash site in the morning, passing checkpoints set at Lu village. Journalists and volunteers were barred from entering, but the brother-in-law of a woman on the doomed flight spoke to Reuters at the checkpoint, while another grief-stricken woman was heard wailing inside a tent.

"All I want is hope, the hope of survival," the 57-year-old man, who gave his surname as Ding, told Reuters. Describing the moment he heard about the disaster, he said: "It was like my heart just dropped."

China had made great strides in improving air safety standards over the past two decades, and Monday's disaster was the first major crash in a dozen years.

Having rushed to Guangxi on Monday to oversee the emergency operations, Vice Premier Liu He held a meeting on Tuesday during which officials were urged to go "all out in their search as long as there is a glimmer of hope". It would be miraculous if anyone was found alive as the plane disintegrated on impact following its plunge from high altitude.

The disaster prompted the aviation regulator to launch a two-week inspection of the sector that will involve checks at all regional air traffic control bureaus, airline companies and flight training institutes to ensure the "absolute" safety.

The broader aviation sector was ordered to carry out special checks to prevent any other major accidents.

Since the crash, China Eastern and two subsidiaries have grounded their fleet of more than 200 Boeing 737-800 jets. The last commercial jetliner to crash in mainland China was in 2010, when an Embraer E-190 regional jet flown by Henan Airlines went down.

At the first news conference held by the government late on Tuesday night in Guangxi, an aviation official said the 737-800 jet that crashed had met airworthiness standards before take-off and crew members had been in good health.

The plane had three pilots on board on its final flight, Zhu Tao, a CAAC official said at the same press conference, which is one more than normally required on a 737.

The aircraft did not respond to repeated calls from air controllers during its rapid descent, Zhu said.

FlightRadar24 data showed the aircraft plunged at a rate of 31,000 feet per minute - the height of a 50-floor building every second.

The disaster comes as Boeing seeks to rebound from several crises, notably the impact of the coronavirus pandemic on air travel and safety concerns over its 737 MAX model following two deadly crashes.

China Eastern also faces deepening losses and closer regulatory scrutiny following the crash.

© RAW 2022

Aged just 25, world No.1 Ash Barty has announced her shock retirement from tennis.

The reigning Australian Open and Wimbledon champion, who hasn't played since breaking the 44-year local title drought at Melbourne Park in January, posted the news on social media on Wednesday.

"Today is difficult and filled with emotion for me as I announce my retirement from tennis," Barty posted on Instagram.

"I am so thankful for everything this sport has given me and leave feeling proud and fulfilled.

"Thank you to everyone who has supported me along the way, I'll always be grateful for the lifelong memories that we created together."

It's the second time Barty has walked away from tennis, with the three-time grand slam champion taking a 16-month sabbatical after a first-round loss at the 2014 US Open.

But, unlike then when she was a homesick teenager, this time Barty says she's quitting for good.

"I will be retiring from tennis. It's the first time I've said it out loud and it's hard to say but I'm so happy and so ready," she said.

"I just know at the moment in my heart for me as a person this is right.

"I've done this before but it's a very different feeling.

"I'm so grateful for everything tennis has given me.

"It's given me all of my dreams plus more but I know that the time is right now for me to step away and chase other dreams and to put the racquets down."

Last time she stopped playing, Barty played professional cricket for the Brisbane Heat in the WBBL.

The sporting super talent could conceivably pursue a professional golf career next.

A four-marker, Barty won the A grade club championship two years ago at Brisbane's Brookwater Golf Club, where she met her now-fiance and PGA trainee pro Gary Kissick.

Both Barty's parents were state amateur golf representatives.

Whatever she pursues, Barty's tennis legacy is secure.

Two weeks after winning the French Open in 2019, Barty became the first Australian woman to reach world No.1 since her mentor and Indigenous idol Evonne Goolagong 43 years earlier.

She followed that up with victory at the 2019 WTA Finals in Shenzhen, in doing so pocketing $US6.4 million - the biggest cheque in tennis history.

Her crowning glory came last year at Wimbledon before Barty defied intense pressure and expectations from home fans to win the Australian Open.

"(Retirement) is something I've been thinking about for along time and I've had a lot of incredible moments in my career that have been pivotal moments," Barty said in a video interview with her great mate and former doubles partner Casey Dellacqua.

"Wimbledon last year changed a lot for me as a person and for me as an athlete.

"You work so hard your whole life for one goal and I've been able to share that with so many incredible people but to be able to win Wimbledon was my dream.

"The one true dream that I really wanted in tennis. That really changed my perspective and I just had that gut feeling after Wimbledon and had spoken to my team about it."

But after a semi-final and two quarter-final defeats at Melbourne Park, Barty had one more piece of unfinished business to tend to.

"There was a little part of me that wasn't quite satisfied, wasn't quite fulfilled and then came the challenge of the Australian Open and that for me feels like the most perfect way, my perfect way to celebrate what an amazing journey my tennis career has been."

That was the Queenslander's 15th career title - and seemingly last.

She would have been chasing a career grand slam at this year's US Open in September.

Instead Barty leaves the sport having held the top ranking for 114 weeks, the eighth-longest tenure in history behind only all-time greats Steffi Graf, Martina Navratilova, Serena Williams, Chris Evert, Martina Hingis, Monica Selesand Justine Henin.

© AAP 2022

Tasmanian Premier Peter Gutwein will be in isolation for seven days after one of his family members tested positive to COVID-19.

Mr Gutwein on Wednesday released a statement, saying he had returned a negative rapid antigen test and would continue to work from home where possible.

"The Deputy Premier, Jeremy Rockliff, will undertake those duties and responsibilities that I would normally perform as premier during Question Time and for matters before the parliament," Mr Gutwein said.

It comes after nearly 20 Tasmanians who had COVID-19 were incorrectly told they had tested negative on their PCR tests.

Tasmania's Health Commander Kathrine Morgan-Wicks confirmed 19 people were on Tuesday wrongly notified.

The department said the error was corrected within three hours.

Ms Morgan-Wicks said the RHH Laboratory was improving its system to ensure another mistake won't happen.

"On behalf of the Department of Health, I apologise for the error and for any inconvenience caused to the recipients of the incorrect results," she said.

Tasmania reported 1825 new cases on Wednesday.

There were no further deaths but 32 people are in hospital.

© AAP 2022

South Australian Premier Peter Malinauskas has reaffirmed election commitments for the state's southeast, including one to visit the region within 72 hours of being sworn in.

Mr Malinauskas travelled to Mt Gambier on Wednesday and said his new government would follow through on its $100 million in election promises for the region.

They include upgrades to the Mt Gambier Hospital, the deployment of more ambulance officers, development of a new technical college and work to improve job opportunities, particularly in the forest and timber industry.

"What really excites me is realising the economic opportunity that exists in this part of our state," the premier told reporters.

"If I could identify one place in our state that has more economic opportunity than anywhere else, it would be here in the Limestone Coast."

His comments came as counting continued after Saturday's poll.

Labor appears set to hold 27 seats in the 47-seat House of Assembly with 15 to be held by the Liberals and five by independents.

Some seats remain too close to call or must wait on the final distribution of preferences.

But former premier Steven Marshall is likely to retain his eastern suburbs seat of Dunstan despite still trailing his Labor opponent by 11 votes.

Pre-poll and postal votes have cut into Labor's lead and are expected to continue to favour Mr Marshall.

The last of the postal votes must reach the Electoral Commission by Friday.

© AAP 2022