LYNN – Firefighters rescued a mother and her two children from the third floor of a burning apartment building during a 3-alarm fire that displaced more than 20 people early Sunday morning.”It’s not an easy thing for a civilian to climb over and down a fire department ladder, that’s for sure, and these guys did a great job getting them over the ladders and getting them down,” Lynn District Fire Chief John Barry said on Sunday.Firefighters responded at 1:53 a.m. Sunday to 11 Breed Square, just east of the intersection of Western and Summer streets, on the report of a fire. Barry said the second alarm was rung at 1:57 a.m. and the third at 2:02 a.m.The fire appears to have started in a first-floor apartment of a building firefighters estimate had 24 occupants; 12 of whom were home at the time, Barry said.He said the building suffered smoke and heat damage throughout, but firefighters confined the fire damage primarily to one of the first-floor apartments.”The guys did a great job initially containing the fire so the rescues could be made,” Barry said. He said firefighters from Saugus, Salem and Swampscott joined city firefighters at the scene while members of five other local departments covered the city’s stations.Barry reported that a Saugus firefighter was taken to Massachusetts General Hospital for heat exhaustion and dehydration and a city firefighter injured his knee but remained on scene. He said he believed the Saugus firefighter was treated and released. He reported the people whom firefighters rescued – a woman, the woman’s 19-year-old son, and the woman’s 9-year-old daughter – were taken to a local hospital and treated and released.”I saw them rescuing the people; it was scary,” said neighbor Margarita Ponte, on Sunday afternoon. Ponte said she awoke to see flames across the street and went outside, afraid it was her son’s house. She said she was relieved it was not where her son lived but she was concerned the other homes in the area were at risk; saying they were all old and dangerous. Ponte reported she saw the firefighters taking the woman and her children and also a dog from the home.”They did a great job,” Ponte said.American Red Cross spokesperson Ashley Studley said volunteers assisted 22 people from five families impacted by the fire with temporary shelter at a hotel, money for food and clothing, comfort kits and one Mickey Mouse doll.The building was boarded up and “uninhabitable” was scrawled across a fluorescent-orange certificate taped to the front door on Sunday afternoon.Barry said the cause of the fire remains under investigation.