North Andover firefighters crossed into Lawrence on Monday to help battle a five-alarm fire that tore through three multi-family buildings, displaced more than 50 residents, and required a dramatic ladder rescue of a man trapped on the third floor.

The fire broke out around 12:45 p.m. at the intersection of Haverhill and Margin streets, sending a smoke plume visible from I-495 and along the Merrimack River. Lawrence Fire Chief Patrick Delaney said crews fielded multiple 911 calls and conducted a primary search of all three buildings as the blaze spread. North Andover and Andover firefighters responded under a standing mutual-aid agreement with Lawrence.

On the third floor of one burning home, a firefighter spotted a man surrounded by smoke, waving from a window. "He had smoke coming out all around him, he was waving for help," Delaney said. "Our crews did a great job getting a ladder up to him. One of our members went up there and assisted him down the ladder." No injuries were reported in the rescue or the broader response.

More than 50 residents were forced from their apartments, and extensive damage means they aren't expected to return anytime soon. The fire's cause and origin remain undetermined, and as of Wednesday, the North Andover Fire Department hadn't released its own statement detailing its crews' role in the response.

Anyone with information about the fire can contact the Lawrence Fire Department or the Massachusetts State Fire Marshal's office.