New York – An explosion flattened two buildings in New York's Harlem neighbourhood, injuring at least 11 people, local media reported.

The cause of the explosion is unknown.

Firefighters battled the blaze and heavy smoke in and around the collapsed buildings - an apartment building and a church - local TV
channel CBS New York reported.

At least 11 people were treated at a local hospital, according to ABC 7 New York.