SAUGUS – Saugus firefighters reported no injuries but a lot of work, in responding to three fires three nights in a row this week.”Monday, Tuesday, Wednesday, it’s been a great week,” said Saugus Fire Chief Donald McQuaid. “The good thing about all this, at least nobody got hurt.”McQuaid said one incident remains under investigation and is considered suspicious, however.The first call came in at 5 p.m. Monday at Laurel Towers on Rice Street. McQuaid said a grease fire on a stove in the building prompted a sprinkler to activate, which put out the flames. The fire occurred on the sixth floor of the building, however, and the sprinkler also dripped water throughout the building.”It went from the sixth floor to the lobby, 36 rooms were affected, fire alarms, smoke detectors,” McQuaid said. He said staff moved about 30 people to Stonehill Estates in Peabody and 20 people stayed with relatives while workers cleaned up the mess. Workers finished Thursday, he said. He said the damage was believed to cost at least $25,000 to repair.”It’s always on the sixth floor,” McQuaid joked.The second incident occurred a little after 11:30 p.m. Tuesday at 26 Longwood Ave. Neighbors called the fire in as two residents were sleeping in the house. The fire was believed to have started in a car and then spread to the garage, which is attached to the house, McQuaid said. But he said the state fire marshal was called in and a dog was brought in to investigate. He declined to divulge further but said the incident could be called suspicious.Everybody in that incident was also unharmed, McQuaid said.Wednesday night, the fire department responded to 10 Laurel St. at approximately 10:40 p.m. A second alarm was quickly rung as firefighters discovered a blaze in a second-floor bedroom.”Everybody was out of house when they got there, which was good, and we were able to knock down the fire pretty quick,” McQuaid said. Firefighters determined an electrical outlet was to blame for the incident, the chief said. He estimated the damage at approximately $60,000.”It’s been a busy week,” McQuaid noted.