2 WORKERS INJURED IN UTILITY BLAST; UNDERGROUND EXPLOSION TRIGGERS POWER OUTAGE.

Byline: Associated Press 

An underground utility vault exploded Thursday night, causing a fire that seriously burned two workers and cut off electricity to residents, authorities said Friday.

The explosion was felt at least a mile away from the vault, in a residential area near the intersection of Via Pacifica and Wiley Canyon roads, said Steve Conroy, a Southern California Edison spokesman.

A 20-minute power outage affected 3,000 Edison customers. As of 8 a.m. Friday, some 300 customers were without power.

The cause of the blast was under investigation, Conroy said.

Charles Good, 48, and Michael Hughes, 50, were in serious but stable condition at the Grossman Burn Center at Sherman Oaks Hospital and Health Center, Conroy said.

They both suffered second- and third-degree burns, Conroy said.

The workers had climbed out of the vault and were about 15 feet away when they turned on a re-energizing switch about 10:40 p.m., Conroy said.

Seconds later, a ``violent eruption'' of a piece of equipment inside the vault caused an explosion and fire. The blast ``blew the lid off the vault,'' shooting flames toward the men, said Edison spokesman Glen Becerra.

``It was quite a blast,'' said sheriff's Sgt. Robert Norlemann, adding that another Edison worker felt the blast even though he was working in Stevenson Ranch about a mile way.