A plane flying from Israel landed at Sofia airport after a bomb threat was received by email, local media reported on Tuesday, The New Arab reports.
Counter-terrorism units were checking the plane for possible explosive devices, BTA news agency quoted Interior Minsiter Secretary General Lyubomir Nikolov as saying.
Meanwhile, a passenger plane from London made an unscheduled landing at Warsaw-Modlin airport in Poland after a bomb threat alert on Tuesday, forcing the airport to close, and another plane from Copenhagen was being checked at Warsaw-Chopin airport.
Security services were verifying the reported threat in Modlin, the airport said in a statement.
"At 9:54 a.m., a bomb threat alert was announced on board an aircraft operating a flight on the route London Heathrow (LHR) – Warsaw Chopin Airport (WAW). At 10:01 a.m., a Boeing 737 MAX aircraft landed at Warsaw/Modlin Airport," it said.