Smoke and haze lingered over Southwest Philadelphia Wednesday morning after a two-alarm fire with smoke visible for miles broke out late Tuesday afternoon, authorities said.

Jim Garrow, a spokesperson for the Philadelphia Health Department, said the city is currently running tests on air samples for toxins, and suggested people with heart or lung problems should avoid exerting themselves until a full analysis of the air is available.

Photos posted on Twitter by the Philadelphia Fire Department showed a large pile of tires burning near 61st Street and Lindbergh Boulevard. The Fire Department said about 100 personnel had been involved starting around 3 p.m. in battling the blaze at what was described as a junkyard.

The fire was declared under control at 5:30 p.m. and no injuries were reported.

The cause of the fire remained under investigation.