Russian authorities say nothing to worry about after explosion at centre housing smallpox and other deadly diseases

An explosion and fire at a Russian facility that handles dangerous diseases like smallpox, anthrax and Ebola has raised safety concerns even as authorities deny any threat.

A gas cannister exploded and started the blaze during renovations on Monday in a decontamination room at the Vector virology and biotechnology state research centre near Novosibirsk, which formerly developed biological weapons.

The building was not damaged and “no work with biological material was being done in the corpus,” the facility said.

A worker was taken to the hospital with burns on 45 per cent of his body and remained there in critical condition, state media reported on Tuesday. Windows were reportedly broken in the blast.

“There can be no panic nor threat,” the mayor of Koltsovo, the research town where the centre is located, told state media, and the emergencies ministry said there was no danger to the population.

But not all local residents were convinced after seeing fire engines racing toward the centre.

“Welcome to the zombie apocalypse,” one posted on a town social media group.

“In 20 years we'll find out what happened from an HBO series,” said another, referring to the popular show about the Chernobyl disaster.

The incident comes after a mysterious explosion at a missile testing site in the Arkhangelsk region killed at least five researchers and caused radiation levels to spike in August and a fire on a nuclear deep-diving submersible killed 14 sailors in July.

Also this summer, one person was killed and thousands were evacuated during a series of explosions at an arms depot in the Krasnoyarsk region.

Greenpeace activist Rashid Alimov told the Telegraph that civilians had not received enough information about the Vector explosion, adding that the incident again revealed a “careless” attitude towards safety at state facilities.

“The context makes us concerned that systematic problems exist that are leading to such incidents happening more often,” he said.

Founded in 1974, Vector became a hub of the USSR's secret biological warfare programme and produced dangerous pathogens like plague for potential attacks.

After the Soviet breakup, the centre refocused on studying the diagnosis and treatment of illnesses like bird flu and Ebola. It is one of only two centres in the world where the smallpox virus has been preserved.

In 1988, the director of Vector's Marburg virus laboratory was infected and died. In 2004, a Vector employee died of Ebola after accidentally pricking herself with a needle while working with animals during an experiment.