SAN DIEGO (CNS) - A late-afternoon blaze caused an estimated $175,000 worth of damage to a City Heights apartment building Tuesday, injured a woman and left a half-dozen people in need of interim housing.

Flames began spreading through a second-floor rental unit at the two- story complex in the 4100 block of 48th Street shortly before 5 p.m., according to the San Diego Fire-Rescue Department.

It took crews about 20 minutes to subdue the blaze.

Medics treated a resident for a burn to her arm, the department's Lee Swanson said.

The American Red Cross was called in to help the displaced people -- four adults and two children -- arrange for lodging. Two lived in the apartment that burned, and the others, including the juveniles, in a ground-floor residence that sustained water damage, Swanson said.

The cause of the blaze was under investigation.