EAST BOSTON (CBS) – Twenty-one people were forced out of their homes by a large fire in East Boston overnight.

The fire broke out around 11:30 p.m. Monday in a third floor apartment at the corner of Orleans and Sumner Streets.

Everyone inside escaped, but two people were taken to Massachusetts General Hospital for smoke inhalation.

Erasmo Gomez, a 17-year-old who lives on the second floor, said he ran to a nearby fire station as soon as he saw the smoke and flames.

“I (got) out without my jacket, just my pants.  I (ran) to the fireman and I was like, ‘I need help, my house is on fire,’” he told WBZ-TV.

Firefighters had a difficult time with frozen hydrants, but were able to put the fire out.

Investigators say the cause of the fire was a portable heater too close to combustible material in a third floor bedroom.

Damage is estimated at $600,000, according to the fire department.