Crews battle blaze at commercial building in Philadelphia's Northern Liberties section

PHILADELPHIA (WPVI) -- Fire crews battled a blaze at a commercial building in Philadelphia's Northern Liberties section Wednesday morning.

Flames broke out around 9:15 a.m. on the 900 block of North Delaware Avenue.

Chopper 6 was overhead where firefighters could be seen on the roof working to ventilate the area as smoke billowed out from inside.

There are no reports of any injuries.

The cause of the fire remains under investigation.