A plane cleaner working at Istanbul's Sabiha Gokcen airport has died in an explosion on board an aircraft.
The cause of the blast, which also injured a second cleaner, is not clear, Turkish news agency Dogan said.
Pegasus Airlines, a Turkish carrier, said the blast occurred at 2.05am local time when no passengers were on board, and it added that operations are continuing normally.
Turkey's state-run Anadolu Agency said police armed with rifles and wearing protective vests imposed tight security at entrances to the airport after the blast, searching vehicles in the area.
The airport operator says the cause of the explosion is under investigation.