Firefighters rescued four people late Saturday night after they became trapped in a burning building on Speirs Street in Westbrook.

Westbrook Fire Chief Andrew Turcotte said two of the occupants of the home were taken to an area hospital, where they were treated for smoke inhalation and released. There were no other injuries reported.

The fire is not considered suspicious and may have been caused by some type of electrical problem, but it remained under investigation Sunday by the State Fire Marshal’s Office.

Turcotte said crews were able to contain the fire to the basement area, but smoke spread throughout the two-story home and the house won’t be livable for at least a few more days.

Firefighters faced a manpower crunch as a result of a convergence of three separate calls to 911 for emergency help within the span of 18 minutes. Westbrook Fire and Rescue also just happened to be at the minimum allowed staffing level of nine firefighters Saturday night, according to a news release posted on the fire department’s Facebook page.

At 11:31 p.m., a person called 911 for help at a Spring Street home after occupants began administering CPR to a family member who had gone into cardiac arrest. One minute later, an individual on Duck Pond Road called 911 and told dispatchers an ambulance was needed for a person in distress. At 11:49 p.m., a 911 caller reported the fire at 25 Speirs St., a home that is located 800 feet from the city fire station. As a result of the multiple calls for emergency responder services, Turcotte said his department requested mutual aid help from Portland, South Portland, Scarborough and Gorham for the Speirs Street fire.

When crews, including off-duty firefighters, arrived at the Speirs Street residence, they used a ladder to rescue a woman trapped on the second floor and helped a second victim, who was trapped on the first floor, get outside to safety. Westbrook police and neighbors used a neighbor’s ladder to help two people trapped on the porch roof of the burning home make it to safety.

Turcotte said the Spring Street resident who needed CPR was transported to Maine Medical Center in Portland and survived.

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