An intense fire swept through an Aspen Hill area apartment building Friday evening, threatening to displace 12 families, authorities said.

Intense fire was poured from an apartment in the 14200 block of Weeping Willow Drive when firefighters arrived around 6 p.m., said Asst. Chief Scott Graham. He said the fire spread upward.

The cause of the fire is under investigation and officials did not have an estimate of the total damage, Graham said. Authorities said about a dozen units in the building may have been damaged or might be without gas service temporarily.