WASHINGTON — Vice President Joe Biden said this morning that authorities on alert for a Sept. 11 anniversary terror threat are more worried about “a lone actor” with a bomb than an extremely complicated plot like the airliner attacks on the twin towers and the Pentagon.

Biden says new information about a possible plot for a car bombing in Washington or New York comes from a “credible source” but isn’t confirmed. Biden says there’s “no certitude.”

He says the government is doing everything possible to guard against any attack, and “all hands are on deck.”

Speaking today on NBC’s “Today” show, Biden advised residents of Washington and New York to “continue your life as normal” and remain vigilant and report any suspicious activity to law enforcers.