SAN FRANCISCO — Pacific Gas & Electric Co. has started sending out informational letters and safety brochures to 2.5 million homeowners and businesses that lie within about 2,000 feet of its natural gas transmission pipelines.

The company has been under fire to provide more information about the location and safety of its natural gas pipelines in the wake of the San Bruno explosion and fire.

The utility says the mailers will ensure customers, neighbors, public officials and first responders have the information they need in the event of an accident.

PG&E's mailers also point people toward online maps showing pipelines' locations and warn them against the risks of digging into lines with construction equipment.

The Sept. 9 pipeline blast killed eight people and destroyed 38 homes.