MARTINEZ, Calif. (KRON) — Contra Costa County firefighters responded to an apartment fire in Martinez that killed one person Wednesday morning, according to officials.

The fire was reported just before 3 a.m. at an apartment building on Foster Street. Crews told KRON4 they saw flames and smoke coming from the second floor of the building.

Officials said two people were trapped inside.

Firefighters initiated a fire attack through the front door of the building, according to officials.

Crews were able to extract both occupants, one by using a ladder to access the back of the building and the other through the front. One of the occupants died at the scene, officials said. The other was taken to John Muir Hospital in Concord for treatment.

Fire officials said it appeared the fire began in the kitchen but it was unclear what caused it.

The investigation is ongoing.

This story is developing and will be updated.