LYNN – Fire Chief Jim McDonald said 40 to 50 people were displaced after a four-alarm fire destroyed two triple-decker homes on Bennett Circle late Tuesday afternoon. A firefighter was treated for minor heat-related injuries, but no other injuries were reported.”There were six total apartments, three in each building,” McDonald told reporters at the scene. “It’s probably some type of rooming-house situation.”Firefighters responded to 12 Bennett Circle and 6-8 Bennett Circle at approximately 4:30 p.m. Tuesday after firefighters at the nearby station saw smoke and rang an alarm, McDonald said.He said that crews arrived on scene to find heavy fire at 12 Bennett Circle and residents already outside the home. Firefighters reportedly helped residents of 6-8 Bennett Circle evacuate that building as flames spread.McDonald said the incident is under investigation, but initial reports suggest the fire started in either the alleyway between the two buildings or on the porch of 12 Bennett Circle. Flames scorched the adjacent side of 6-8 Bennett Circle, with damage extending almost completely to the back of the house and the roof.McDonald said firefighters faced two main challenges fighting the blaze: access to the site and the heat.Although named Bennett Circle, the street is really a narrow dead-end off of Park Street and behind the Connery American Legion Post #6 on North Common Street. McDonald said ladder trucks could not fit in front of the building, so crews had to find parking lots or undeveloped land adjacent to the site from which to extend ladders, and engines ran long water lines from Park Street.The weather also presented a challenge.”The heat is brutal today,” McDonald said. “It’s not the hottest day of the year, but you get that equipment on?”Sixty-five firefighters responded to the scene to fight the fire, McDonald said, running shortened shifts because of the heat. But only one minor injury was reported. A firefighter was treated at the scene for heat exhaustion, McDonald said.The chief said the buildings were destroyed and personnel would remain at the scene for hours investigating the blaze.American Red Cross workers reported helping residents displaced by the blaze, and the organization opened up a shelter at Lynn Classical High School.