It wasn't a formal invitation, but it was an invitation nonetheless.

While attending a barbecue for firefighters in Shanksville, Pennsylvania, Tuesday, Vice President Joe Biden came across Brad Shober, the deputy fire chief, who he met at last year's ceremony commemorating the tenth anniversary of the September 11 terror attacks.

Biden, who also hosted Shober and other Shanksville firefighters at his residence in Washington last year, told the deputy chief and other firefighters assembled he wanted them to come back to the nation's capital for a second visit.

"He's going to call you, no (expletive)," Biden said, pointing to an aide.

Noticing reporters, the vice president changed his terminology.

"This is no malarkey," Biden said. "You come to the White House. I'll buy you a beer."

Biden eventually found himself at the grill, where he helped himself to a hamburger with a slice of American cheese. His $20 donation to the firefighters also covered the lunch of Interior Secretary Ken Salazar, who, along with Transportation Secretary Ray LaHood, traveled to Shanksville with Biden.

Earlier in the day, the vice president spoke at a remembrance ceremony near the crash site of a flight hijacked on September 11, 2001 -- eleven years ago Tuesday.

"What they did for this country is still etched in the minds of not only you, but millions of Americans forever," Biden said of passengers on Flight 93 who forced the hijackers to crash the plane believed headed for a suicide attack on the U.S. Capitol.