Hoping to fill a ``gaping hole'' in homeland security, U.S. Rep. Tom Lantos of San Mateo unveiled legislation Tuesday that would require local police agencies to install security alarms and cameras at their storage bunkers for high explosives -- and to report what they're storing to the federal government.

The bill was prompted by outrage over the theft last summer of 200 pounds of powerful explosives from a law enforcement bunker near the Crystal Springs Reservoir. The depot, used by the San Mateo County Sheriff's Office, the San Francisco Police Department and the FBI, had an alarm that had been out of order for at least 10 years. A thief broke through fencing and a lock to enter the depot undetected twice during the Fourth of July weekend.

Four suspects have been arrested and the munitions recovered. The thieves were apparently planning to sell the explosives on the black market and use the money allegedly to pay for a drug habit, sheriff's officials said, and there was no threat of terrorism. The unguarded bunker has been closed down.

Despite the peaceful ending, the theft prompted a furor and a rare hearing in San Mateo by the House national security subcommittee chaired by Rep. Christopher Shays, R-Conn.

Lantos and Shays said they were appalled to learn that the federal Bureau of Alcohol, Tobacco, Firearms and Explosives had no idea how many police agencies across the nation store explosives nor where the depots are located.

On Tuesday, Lantos and Shays introduced the bill requiring security systems and establishing the first federal oversight of explosives stored by police agencies; currently only private companies are regulated.

``It's absurd to talk about homeland security in the abstract, to move from yellow to orange, while not dealing with a gaping hole in our homeland security system, namely the storage of explosives by public entities,'' Lantos said Tuesday. He was referring in his statement to the color system used to indicate the danger level of a terrorist attack.

The bill would give each state six months to report to the U.S. attorney general the locations of all explosives stored by local law enforcement agencies. The attorney general would establish deadlines for agencies to outfit the facilities with cameras or alarms and would have the right to inspect them.

The bill would pay police agencies up to 50 percent of the cost of installing the security systems. It also threatens the agencies with a reduction of 10 percent of their homeland security grants if they fail to comply.