HARTFORD, Conn. (AP) – Fire broke out in a factory in the city’s north end Thursday night, spreading quickly and prompting officials to warn neighbors of possible toxic fumes.

The three-alarm fire was reported about 5:30 p.m. in Machinery Services, described as a heat treating shop.

More than 50 Hartford firefighters responded and departments from neighboring towns were put on alert. The state Department of Environmental Protection also was called to the scene.

Black clouds of smoke billowed across the area and early on could be seen for miles. Several roads around the fire were shut down.

No injuries were reported.