Russian national charged after allegedly flying to US with no passport or ticket

A Russian national was charged after allegedly sneaking onto a plane in Denmark bound for Los Angeles International Airport -- and not telling the FBI why he was headed for the United States.

Sergey Vladimirovich Ochigava allegedly flew to LAX from Copenhagen, Denmark, on Nov. 4 despite not being on the flight manifest, according to a criminal complaint.

Ochigava "was unable to produce a passport or a visa to enter the United States," according to the complaint. When questioned by authorities, Ochigava "gave false and misleading information about his travel to the United States, including initially telling CBP that he left his U.S. passport on the airplane," the complaint says.

During the flight, Ochigava was observed switching seats, eating "two meals during each meal service, and at one point attempted to eat the chocolate that belonged to members of the cabin crew," the complaint says.

The complaint says Russian nationals must have a valid visa and passport to enter the U.S. When authorities searched his bag, Ochigava allegedly had some parts of a passport and an Israeli ID card but nothing complete. When officers allegedly tried to run his name, nothing came up, according to the complaint.

In an interview with the FBI, Ochigava allegedly said he had a PhD in economics and marketing from a Russian university.

Ochigava "claimed he had not been sleeping for three days and did not understand what was going on and "stated he might have had a plane ticket to come to the United States, but he was not sure," according to the complaint.

The Russian said he could not remember how he got on the plane and would not explain how or when he got to Copenhagen or what he was doing there, the complaint adds. He allegedly said he could not remember how he got on the plane.

A lawyer for Ochigava did not respond to ABC News' request for comment.