By MICHAEL HOWARD SAUL

New York City Mayor Michael Bloomberg, joined at City Hall by other area mayors and U.S. Rep. Pete King, outlined on Tuesday a series of steps to prevent another shooting tragedy following the assassination attempt of an Arizona congresswoman.

Mr. King, a Long Island Republican and chairman of the House Committee on Homeland Security, said he will introduce legislation that would make it illegal to knowingly carry a gun within 1,000 feet of high-profile federal officials.

"Based on what we know so far, the system that is supposed to protect us from dangerous and deranged people has failed once again," Mr. Bloomberg said at a news conference nearly 72 hours after accused killer Jared Lee Loughner opened fire on Rep. Gabrielle Giffords (D., Ariz.), gravely wounding her and slaying six others.

Mr. Bloomberg, co-founder of Mayors Against Illegal Guns, a coalition of more than 550 mayors, said the shooting massacre in Arizona exposed dangerous cracks in the country's firearm background-check system. These gaps, he said, must be addressed and the federal government must do a better job of sharing information.

"This case," said Mr. Bloomberg, referring to the Tucson, Ariz., shooting, "is fundamentally about a mentally ill drug abuser who had access to guns and shouldn't have." The accused gunman was a chronic drug abuser who was arrested on a drug-related charge and rejected by the U.S. Army because of his drug history, Mr. Bloomberg said.

In Tucson, the Army was aware that Mr. Loughner was a chronic drug abuser but as of yet there is no indication it informed the Federal Bureau of Investigation, Mr. Bloomberg said. The federal National Instant Check System regularly omits records of those who should be prohibited from possessing a gun, he said.

"Drug abusers and addicts are prohibited by law from buying a gun but the [government's] definition of what constitutes an addict or abuser is complicated and confusing," the mayor said. "That's one of the reasons why as of Dec. 31, only 2,092 people were listed in the background-check database as an addict or abuser, even though thousands and thousands of people with drug records should have been in that database, including quite possibly the man who pulled the trigger in Tucson."

Mr. King called the Tucson incident a "bitter attack against democracy" and said his proposed legislation is needed to ensure contact between elected officials and constituents. The officials to be covered under his legislation include the president, vice president, members of Congress and federal judges.

NYPD Commissioner Ray Kelly said 65% of murders in the city stem from illegal handguns, and 90% of the guns confiscated in New York come from outside the state. "This is a national problem that cries out for a national solution," he said.

Rachel Parsons, a spokeswoman for the National Rifle Association, said, "At this time anything other than prayers for the victims and their families would be inappropriate."