TALLINN — Estonian Air received a bomb threat Monday which ended up being a prank, but caused the delay flights to Copenhagen, Oslo, and Stockholm.

Police have initiated an investigation on a person who called an emergency call center number Monday at 6:20 p.m. claiming that there was a bomb in an Estonian Air aircraft. The person’s gender and other details are not being released.

Bomb squad crews conducted a search in three airplanes in at Tallinn International Airport, finishing around 9 p.m. with nothing dangerous was found. Estonian Air tightened its security checks Monday in light of the incident.

Another Estonian Air’s aircraft was searched at Vilnius International Airport, shortly after its arrival as the caller claimed 200 grams of TNT were on board.

Passengers were searched by police at the airport building, and their luggage searched, but no explosives were found.

A lot of trouble for a bad joke

Estonian Air is planning to give a material damage claim to the person who made the bomb threat. The person will have to pay the costs of reformulating the passengers to the connecting flights, accommodation, catering, transportation and other related fees.

Police have not named any suspects nor named any arrests.

“No suspects have been interrogated concerning the bomb threat,” Harrys Puusepp, a press spokesman of Northern Police Prefecture told Baltic Reports.