No threat to U.S. seen in London's scare

WASHINGTON — Unexploded car bombs in London led to extra patrols in the United States on Friday, but Bush administration officials said they saw no special terrorist threat heading toward the Fourth of July holiday.

Homeland Security Secretary Michael Chertoff urged Americans to be vigilant but said there were no plans to raise the U.S. national threat level from yellow, for elevated.

White House press secretary Tony Snow said: "There is no specific or credible evidence of any threat of any kind against the United States of America." He was in Kennebunkport, Maine, where President Bush will meet Sunday with Russian President Vladimir Putin.

Snow said British authorities had not determined if there was a link to any terrorist group.

"Look, it's terrorism, but ... there's no established connection with any organization at this point," he said. Snow said U.S. officials "remain very aggressively engaged" with the British.

Bush was briefed in Kennebunkport about the London investigation. At the White House, Homeland Security adviser Frances Fragos Townsend called a meeting of top officials, inviting Chertoff, Vice President Dick Cheney, Secretary of State Condoleezza Rice, Defense Secretary Robert Gates, CIA Director Michael Hayden, Treasury Secretary Henry Paulson and Attorney General Alberto Gonzales, among others.

Throughout the country, local law-enforcement agencies received two FBI bulletins, according to an official who summarized them. The first said that authorities had no credible evidence an attack was planned for the Fourth of July. The second advised local officials to be on the lookout for suspicious vehicles and activity.

In New York, Mayor Michael Bloomberg said police would work extra hours in more locations.

"We're going to ramp up a little bit, but nothing dramatic," Bloomberg said on his weekly radio show.