Montgomery County fire investigators are trying to determine what caused an early morning fire in Derwood.

At 4:17 a.m. on Friday, firefighters responded to a report of a fire in a two-level single-family home in the 7500 block of Julia Terrace, said Capt. Oscar Garcia, a county fire and rescue service spokesman.

A search of the home found no occupants, Garcia said.

“Initial reports are that they were evacuating and exiting safely when firefighters arrived on the scene,” he said. Further information about the residents was not immediately available.

The fire appeared to originate in the home’s carport, Garcia said.

It took firefighters about 10 minutes to bring most of fire under control. “However they had to continue to look for any extension into the house” from the carport that created spots of fire on the first and second floors, Garcia said.

The fire appeared to by fueled by a source in the carport, he said.

Damage estimates were not immediately available.