A Russian man who flew on a plane from Denmark to Los Angeles in November without a passport or ticket told US authorities he did not remember how he got through security in Europe, according to a federal complaint filed by the FBI.

Sergey Vladimirovich Ochigava arrived at Los Angeles International Airport on Nov. 4 via Scandinavian Airlines flight 931 from Copenhagen. A U.S. Customs and Border Protection officer could not find Ochigava on the flight manifest or any other incoming international flights, according to the complaint filed Nov. 6 in Los Angeles federal court.

He was charged with being a stowaway on an aircraft and pleaded not guilty in a Dec. 5 arraignment and remains in custody. A trial has been scheduled for Dec. 26.

The flight crew told investigators that during the flight’s departure, Ochigava was in a seat that was supposed to be unoccupied. After departure, he kept wandering around the plane, switching seats, and trying to talk to other passengers, who ignored him, according to the complaint.

He also ate “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.

Ochigava did not have a passport or visa to enter the United States, officials said. Customs and Border Protection officers searched his bag and found what “appeared to be Russian identification cards and an Israeli identification card,” federal officials said in court documents. They also found in his phone a photograph that partially showed a passport containing his name, date of birth, and a passport number, but not his photograph, they said.

Ochigava “gave false and misleading information about his travel to the United States, including initially telling CBP that he left his US passport on the airplane,” the complaint says.

Scandinavian Airlines confirmed that “there has been a situation regarding a passenger” on a flight from Copenhagen to the United States. “The matter is being handled by relevant authorities both in US and Denmark and we cannot comment any further,” the airline said in a written statement.

Ochigava told FBI agents he has a doctorate in economics and marketing and that he had last worked as an economist in Russia.

“Ochigava claimed he had not been sleeping for three days and did not understand what was going on,” the complaint said.

He told officials he might have had a plane ticket to come to the United States, but he was not sure. He also said he did not remember how he got through security in Copenhagen and would not explain what he was doing in the Scandinavian city, according to the complaint.