Firefighters help one of their own down a ladder after he was injured battling a fire at 33 Washington St. in Ayer on Wednesday. SUN/SCOTT LAPRADE

AYER — Two people, including an Ayer firefighter, were sent to the hospital with non-life-threatening injuries following a blaze that broke out late Wednesday morning.

The names of the injured were not released by Ayer Fire Lt. John Bresnahan.

The cause of the blaze, involving a barn behind the home at 33 Washington St., remained under investigation on Wednesday night.

The fire was first reported to emergency responders around 11:40 a.m. with the final crew leaving the property at around 4 p.m., according to Bresnahan.

The structure was still steaming mid-afternoon with most of the roof gone. From the street, the damage seemed to be contained to the outbuilding.

Ayer was assisted by fire departments from Westford, Lunenburg, Devens and Littleton through mutual aid. The rehab unit from the state Department of Fire Services Specials Operations was at the site.

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