MOSCOW, March 22 (RIA Novosti) - One person died and seven were injured Friday in an incident that involved a household gas explosion in a residential building in the Russian northwestern city of St. Petersburg, Russia’s Emergencies Ministry reported.

The explosion apparently occurred inside an apartment on the fourth floor of a nine-story residential building in the city’s northeast, causing a fire. It was not immediately clear what could have caused the blast.

Earlier it was reported that eight people were injured, but one of them later died in a hospital, a ministry spokesman said.

Residents of apartments in the damaged part of the building were evacuated and temporarily accommodated at a school.

An investigation is underway.

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