Christian Longo, accused of killing his wife and three children and dumping their bodies into the Pacific — is believed to have fled to Mexico, the FBI said Friday.

Using a stolen credit card and identification, Longo purchased an airline ticket at San Francisco's airport on Dec. 27 for Cancun, Mexico, said Charles Mathews, the FBI's special agent in charge in Oregon.

Mathews announced that Longo has been placed on the FBI's Ten Most Wanted list, and has offered a $50,000 reward for information leading to his arrest.

Longo is accused of killing his wife, MaryJane Longo, 34, and three children, Zachary, 4, Sadie Ann, 3, and 2-year-old Madison. Their bodies were found in the coastal waters of Waldport and Newport between Dec. 19 and Dec. 27.

After vanishing from Oregon, Longo was spotted at a San Francisco coffee shop on Dec. 23, then spent the nights of Dec. 23 and 24 in a city youth hostel. He was seen again in San Francisco on Dec. 26.

The Dodge Durango Longo had been driving — which was stolen from an Oregon car lot — was found at San Francisco International Airport last Sunday.

Longo — who has a history of petty theft and debt — is believed to have purchased a plane ticket to Cancun on Dec. 27 using identification "fraudulently obtained" from an Oregon man, Mathews said.

"He's accomplished at changing his identity and assuming other people's identity," Mathews said at a news conference.

Before fleeing, Longo worked for a Starbucks in Newport.

Starbucks issued a statement this week saying Longo failed to show up for a Dec. 28 job interview at one of its shops on Union Street in San Francisco. Between Jan. 2 and 4, Longo also applied for work at a Starbucks near Santa Cruz, Calif., according to the statement.

Police have not divulged a possible motive for the slayings.

Longo, who owned a construction cleaning business in Michigan, has been named in six lawsuits seeking more than $30,000 and is wanted on two warrants in Michigan for probation violation and a charge of larceny by conversion.

The Longos reportedly left $60,000 in debts in Michigan when they moved west.

The last suspect from an Oregon crime to make the Ten Most Wanted list was Edward Wayne Edwards, a suspect in two killings who escaped from a Portland jail in 1960. He was captured by Atlanta police in 1962.

The Ten Most Wanted list sometimes has more than 10 fugitives. Longo is the 11th person on the list, along with Usama bin Laden.

Producers of the television program "America's Most Wanted" said they will have a segment featuring Longo Saturday night.