The startling images from the city where the virus broke out were published by the state-owned China Daily on Twitter last month before being swiftly deleted.

They had been released first in 2018 before re-emerging and causing concern over how the virus came to spread all over the world.

The picture of the fridge-freezer shows a flimsy loose seal on the door, as a lab worker pulls out a chilled box containing deadly samples while wearing gloves and a mask.

Shocking photos inside Wuhan lab show broken seal on unit storing 1,500 virus strains including bat coronavirus

US and British intelligence officials suspect bungling scientists at the Wuhan Institute of Virology accidentally spread the killer during risky coronavirus tests on bats.

In January 2018, the US Embassy in Beijing sent two official warnings back to Washington highlighting inadequate safety measures at the Wuhan lab where scientists conducted dangerous research on coronavirus from bats, The Washington Post reported.

They warned about safety and management weaknesses at the lab and proposed more international assistance as the Chinese had turned down help to prove their ability to work independently.

Other reports have also emerged alleging China attempted to cover up its role in the extent of the pandemic by silencing whistleblowers and muzzling scientists, while concerned doctors have disappeared.

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