This is an archived article and the information in the article may be outdated. Please look at the time stamp on the story to see when it was last updated.

An explosion caused by an electrical vault injured four people and triggered power outages in the Hollywood area early Tuesday morning, fire officials said.

The blast was reported about 1:35 a.m. at 6198 Franklin Avenue near the 101 Freeway, according to a Los Angeles Fire Department alert.

Two people were taken to a hospital, one in serious condition and another in moderate condition, according to LAFD. The other two people declined transport to hospitals.

Fire officials warned that the explosion may have knocked out power for some residents in the area.

By 8 a.m., more than 1,000 customers were affected by an outage in the area and crews estimated it would be restored by 1 p.m., according to the Los Angeles Department of Water and Power.

Police and fire investigators responded to the scene to investigate.

It’s unclear what sparked the blast and no further details were immediately available.