Two killed, 22 injured in New York building explosion

At least two people were killed and 22 injured when a powerful explosion levelled two residential buildings in New York's East Harlem neighbourhood Wednesday morning. Over 12 people remained missing, authorities said.

The blast struck a building at 116th Street and Park Avenue in Upper Manhattan at about 9:30 a.m. local time (1330 GMT), blowing out windows in surrounding buildings and sending debris crashing down onto nearby streets, Xinhua reported.

Two five-storey residential buildings next door to each other collapsed in the incident, with one essentially gone from the blast.

At least 12 people remained missing so far, and two of the wounded had life-threatening injuries, fire officials said, indicating that the death toll could rise further.

Hours after the explosion, smoke and ashes from the explosion can still be seen pouring into the neighbourhood where about 250 firefighters were battling to extinguish heavy blaze.

Preliminary investigation suggested that the only warning came before the blast is a call about a gas leak.

Utility company Con Edison said it received the call from a resident in an adjacent building about 15 minutes before the explosion. The company said it sent two crews to the scene after the call, but they arrived just after the explosion.

New York Mayor Bill de Blasio said that "the explosion was based on a gas leak. The impact affected buildings around the two that were destroyed, very heavy impacts on the surrounding buildings. A heavy fire has ensued as well."

"There will be a search through the rubbles of the building as soon as the fire is put out looking for those who are missing," de Blasio said.

In the immediate aftermath, witnesses described a chaotic scene with people in panic and a serious fire spewing out thick smoke.

Gregory Garcia, who was just a block away from the scene before the explosion, said he was shocked by a huge explosion. Everyone was running in panic unsure what had happened, he said.

The two collapsed five-story buildings had a piano store and a Spanish Christian Church on the ground floor and apartments on the upper, Garcia said.