A Los Angeles firefighter was killed and another critically injured Wednesday afternoon after they were apparently hit by exploding manhole covers while responding to a call in Westchester, a department spokesman said.

The firefighters were called to Sepulveda and La Tijera boulevards at 1:57 p.m. after a report of smoke from a possible fire. Once they arrived, there was a larger explosion, and they were hit by the manhole covers, said Ron Myers, spokesman for the Los Angeles Fire Department. Firefighters called in a rescue helicopter to fly the injured individuals to a nearby hospital, Myers said.

Just before the blast, officials noticed smoke coming from two manhole covers.

The names of the firefighters have not been released, Myers said.

The blast also significantly damaged a bank building on Sepulveda Boulevard. TV footage showed the front of the building sheered off.

No other details about the incident were immediately available.

bob.pool@latimes.com

molly.hennessy-fiske@latimes.com