A decades-old gas main may have fed the explosion and fire Thursday that destroyed homes and killed or injured residents of the Crestmoor Canyon area of San Bruno.

A 30-inch diameter gas pipe is the likely culprit behind the massive explosion that rocked the community at 6:15 p.m. Thursday, although crews have not been able to get close enough to the source to determine the exact cause, PG&E President Chris Johns said this morning.

Over the coming weeks, the National Transportation Safety Board will conduct an independent investigation into the explosion. Johns said PG&E is "committed to work with them."

He hazarded a guess that the pipe could be as old as 50 years, but said he would need to defer to records to confirm its age.

State and local elected officials joined the San Bruno police and fire chiefs Friday morning (Sept. 10) at a press conference to answer questions as the smoke cleared from smoldering wreckage.

Acting as the state leader while Gov. Arnold Schwarzenegger is conducting business in Asia, Lt. Gov. Abel Maldonado declared the fire-ravaged area an emergency disaster Thursday night, opening up state resources to assist in the recovery effort.

Maldonado confirmed that the fire has charred 15 acres of land, and is still only 75 percent contained, up from 50 percent contained overnight.

The blaze ripped across the San Bruno neighborhood, hopping from home to home, destroying 38 structures and significantly damaging seven others.

Reports from Thursday night indicated some 120 homes had been damaged. Fire chief Dennis Haag confirmed today that dozens of homes sustained damage, as was determined by an aerial survey of the area.

"Without warning, many of these people's lives have been changed forever and my deepest prayers go out to everyone," Maldonado said.

The extent of property losses, which insurance adjusters are estimating could reach the tens of millions, is shadowed only by the loss of human life: four people were confirmed dead by the San Mateo County coroner's office this morning.

A total of 52 victims were treated at area hospitals, with four people transferred to a burn center in San Francisco -- three of those patients were critically burned.

Four firefighters suffered from smoke inhalation at the start of the fire, which was a six-alarm blaze battled by local, county and state emergency response teams. Those firefighters were transported to a local hospital and released two hours later, Haag said.

Walking the site in the daylight this morning, Haag said the extent of the damage was some of the worst he's seen during his career.

"It looks like a moonscape in some areas," he said.

A 30-inch diameter gas pipe is the likely culprit behind the massive explosion that rocked the community at 6:15 p.m. Thursday, although crews have not been able to get close enough to the source to determine the exact cause, PG&E President Chris Johns said this morning.

Over the coming weeks, the National Transportation Safety Board will conduct an independent investigation into the explosion, and Johns said that PG&E is "committed to work with them."

He hazarded a guess that the pipe could be as old as 50 years, but said he would need to defer to records to confirm its age.

Despite the enormous losses, many of the speakers expressed gratitude in the way emergency responders and members of the community came together to quickly respond to the crisis.

"As devastating as this was, it could have been so much worse in my opinion," Haag said. "We made a terrific effort in stopping the fires in the way we did."

More than 60 pieces of equipment were deployed in the response, including 21 local fire engines, 18 Cal Fire engines, 20 California Emergency Management Agency vehicles, and four air tankers, which were dispatched to the scene immediately Thursday night, Maldonado said.

Thirty more fire engines are expected to arrive at the scene today.

Beyond the immediate response, officials are already orchestrating plans to assist the hundreds of affected individuals in the long term.

"You've heard the numbers, but what we have to deal with in the immediate future is the stress, the anxiety, the uncertainness in the minds of those that have been affected," San Bruno Mayor Jim Ruane said.

The immediate emergency designation by Maldonado allows for certain state funding to flow into the charred community, but U.S. Rep. Jackie Speier said that federal officials were working to secure additional federal emergency funds.

Seeking a Federal Emergency Management Agency designation means that residents will benefit from an array of services, including housing, medical care, small business loans and assistance in filing insurance claims, Speier said.

As much as money is needed to rebuild the community, the strength of the shell-shocked community has been powering efforts so far.

"It was rather gut-wrenching to me that these strangers and these individuals would come out in the middle of the night ... to help their fellow neighbors," said Sen. Leland Yee, whose district includes San Bruno.

Yee, who recalled the devastation of the 1991 Oakland Hills fire, said that his office was committed "to doing whatever we can to help this city and this county rebound."

"It's very tight-knit, generations of families have lived here forever. We will all come together," Speier said. "We will once again see San Bruno thriving."

Assemblyman Jerry Hill was also on hand this morning, adding that "this community came together from a public safety stand point, and is coming together now from a personal standpoint."

Hill said, "It has been a tough struggle, but this city will rise again through this and it will be stronger than ever."

According to City Manager Connie Jackson, some blocks were harder hit than others. The damage was the most serious on the 1600 and 1700 blocks of Claremont Drive; the 900 block of Glenview Drive; the 1700 block of Earl Avenue; the 1100 block of Fairmont Drive; and the 2700 block of Concord Way.

Significant sections of the neighborhood have been deemed safe for residents to return to, said Jackson, who stressed that evacuated residents should still check in at Veterans Memorial Recreation Center at 251 City Park Way.

Police are treating the entire area as a crime scene to preserve the evidence until investigators can access the rubble and take a closer look at the ruptured gas line, police Chief Neil Telford said.

PG&E president Chris Johns said that their crews are working to secure the area and restore gas and electricity service to hundreds of customers who lost power after the explosion.

More than 40 PG&E members worked overnight to survey the integrity of the lines throughout the surrounding neighborhoods and ensure the safety of residents.

As of 6 a.m., 700 electricity customers and 300 gas customers were experiencing a lack of service. Johns estimated that 300 electricity customers would have power restored by noon today, and that the delay was due to the labor-intensive nature of the restoration.

"We're having to walk block-by-block, house-by-house to establish service," he said.

It has yet to be determined whether PG&E is to blame for the disaster, but Johns said in the meantime the company is committed to providing the community with resources and relief, and is working with the American Red Cross to do so.

"We're really saddened and sorry about this tragedy," Johns said.

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