Russia's Emergency Ministry rescuers work at the blast site at the Avangard fireworks factory in Gatchina outside Saint Petersburg on October 19, 2018. (AFP PHOTO)

MOSCOW, Oct. 19 (Xinhua) -- Two people were killed in an explosion at a fireworks factory in the Gatchina district of Russia's Leningrad region, Russian media reported Friday.

The explosion occurred at 4:48 p.m. Moscow time (1348 GMT), causing a partial collapse of the factory's building, Russia's Emergencies Ministry said in a statement.

Two bodies were found under the debris, and two injured people were taken to hospital, Russian news agencies quoted the ministry's spokesman as saying.

Several other people may still be under the rubble, according to the reports.

The emergencies ministry said the explosion was caused by technical reasons.

An investigative team has been sent to the scene of the accident, according to a statement by Russia's Investigative Committee.

A criminal case has been initiated on the grounds of violations of safety rules at explosive objects, it said.