BETHLEHEM, Pa. (CBS) — A three alarm fire burned through a Bethlehem warehouse Wednesday morning.

Bethlehem police say a shelter in place order has been declared for the surrounding areas. Residents are being told to keep windows closed due to excessive smoke.

The fire was reported shortly before 4 a.m. in a large warehouse on Mauch Chunk Road. The fire department has closed nearby streets as fire crews tackle the blaze.

There is a shelter set up nearby at James Buchanan Elementary School at 1621 Catasauqua Road.

Smoky conditions remain, but there are no reported injuries.

Firefighters say nobody was inside when the building ignited, but some employees showed up to the scene in shock.

Crews had to cut power supply to 300 area homes and parts of Moravian College’s campus for much of the morning.

“Approximately six hours the power was shut down for the safety of our firefighters here,” said Bethlehem Fire Chief Bob Novatnack.

Since the warehouse handled sheet metal and oils, firefighters say it continued to smolder through the afternoon. Emergency management crews are closely monitoring the air quality.

“It’s definitely going to be obnoxious, an obnoxious smell to them, but the content of what they’re breathing in is nothing that they should be concerned with,” said Jeff Steiert of Northampton County Emergency Management.

Crews will be out monitoring the air quality throughout the rest of the evening. Crews will also be cleaning up.