One dead, one wounded after explosion at Istanbul airport

One woman has died and another is wounded after an explosion at an airport in Istanbul, according to local media reports.

Airport cleaner Zehra Yamac, 30, died of head wounds hours after the blast on the tarmac at Sabiha Gokcen airport, on the Asian side of Turkey's largest city, CNN-Turk and NTV television reported. The surviving victim is also believed to be a cleaner. 

Security forces and firefighters rushed to the airport after the explosion happened just outside the terminal building about 2am local time.

Authorities are investigating the cause of the blast, which is unknown. 

The two Pegasus Airlines cleaners were nearby when the explosion happened, the private Turkish airline confirmed in a statement.

"There were no passengers either on the plane or on the stairway," the statement read.

"Sabiha Gokcen airport is continuing its normal operations."

The airport is the second international airport in Istanbul, after Ataturk Airport on the European side of the city.

"We are working very closely with the Turkish government and our counterparts to facilitate the investigation, and we await their official report on it," airport executive director Dato' Azmi Murad said in a statement.