DHS steps up mass transit, airport security

The Homeland Security Department is bolstering airport and mass transit security following an airport attack and two thwarted car bomb attempts in the United Kingdom over the weekend, a spokesman said Monday.

DHS Secretary Michael Chertoff said the department will be increasing security for mass transit systems, airports and other transportation sites, "in an abundance of caution during this holiday period." But Chertoff said there is no credible threat against the United States at this time.

DHS spokesman Russ Knocke said there has been increased air marshal coverage and tightened security for public transportation since last August's foiled plot to bomb U.S.-bound planes.

"The focus is on transit security," Knocke said. "It's summer, and we've seen attacks on transit systems in London and Madrid."

Knocke reiterated that there are no ongoing, credible threats to the United States now.

Chertoff said DHS will not raise the national terror alert level unless the department receives specific intelligence about a possible threat in the United States. He noted, however, that the threat level for the airline sector has been at orange -- the second highest level -- since last summer.

A Transportation Security Administration official confirmed that airports and airlines have been on high alert for almost a year. Ongoing security measures include the use of air marshals, canine handlers and random vehicle searches.

"We're doing the same things we've been doing, just more of it," the official said.

While TSA is responding to the U.K. incidents, staffing levels typically increase around holidays anyway, the official said.

Security in general is tight in anticipation of the Fourth of July, but DHS is allowing state and local authorities to take the lead on any extra measures at local celebrations.

"There has been no adjustment to the federal security posture for holiday activities this week, but we support fully any steps local officials deem appropriate," Knocke said. Chief Dwight Pettiford said the Park Police is working closely with DHS to ensure that it is aware of any threats to the Washington Fourth of July celebration. The Park Police is the lead law enforcement agency for the event.

"We're in constant contact with the Department of Homeland Security -- constantly, daily," Pettiford said.

Knocke said DHS has been working extensively with U.K. officials to remain apprised of any new information pertaining to the United States.

"We are in constant communication with U.K. counterparts, and it's been that way for years, particularly going back to last August," Knocke said. "We're very fortunate to have a strong, robust partnership with our U.K. counterparts. When we get information it's shared with them almost instantaneously and vice versa."