Polish airline LOT reported that Bulgarian company Electra Airways was operating a flight from Warsaw to Tel Aviv when the crew reported an emergency situation.
"This report was later canceled after contact with air traffic controllers," said airline spokesman Krzysztof Moczulski.
A statement from the Bulgarian Ministry of Defense said the aircraft transmitted squawk code 7500, an emergency signal indicating unlawful interference or hijacking.
Sofia also scrambled a MiG-29 fighter jet to intercept the aircraft and escort it through Bulgarian airspace.
The flight was diverted to Burgas, Bulgaria, where Electra Airways is based, Moczulski said.
According to the Israeli military, two air force fighter jets were scrambled toward the civilian aircraft over the Mediterranean Sea after receiving a report of lost communication with the aircraft. The military later said the incident was not security-related.
"In this situation, we have no reason to take action," said Piotr Rudzki, a spokesman for Warsaw's Chopin Airport. According to him, the Bulgarian airline reported a pilot error, "so we don't need to take any action."
"We are monitoring the situation; nothing indicates any (external) interference," he added.
