MOSCOW (AP) — A gas explosion in an apartment building outside Moscow on Wednesday killed two people and injured five others, law enforcement officials said.

The blast occurred in a nine-story building in Noginsk, a town 50 kilometers (about 30 miles) east of Moscow. The blast affected the lower part of the building, with three stories appearing to have sustained the most damage. About 30 apartments were damaged. Local authorities evacuated 170 people from the building.

A man and a woman were killed, and five other people sustained injuries, according to the Moscow region's branch of Russia’s Investigative Committee. It wasn't immediately clear whether there were more people under the rubble.

The authorities launched a criminal probe into the explosion as is common in such cases. The governor of the Moscow region, Andrei Vorobyov, headed to the site of the blast.

The Associated Press