An airplane cleaner at Istanbul’s Sabiha Gokcen airport has died of her injuries after an explosion on the tarmac on Wednesday morning, local media reported.

The cause of the blast, which also injured a second cleaner, was not immediately clear.

Budget carrier Pegasus said the explosion took place next to one of its planes, at 2:05am on Wednesday morning. It added that no passengers were in the area at the time of the blast and that its operations at the airport would continue normally.

According to state-run Anadolu Agency, police armed with rifles and protective vests imposed tight security at the airport Wednesday, searching vehicles while a police helicopter circled overhead.

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

Sabiha Gokcen airport, named after Turkey's first female fighter pilot, is the second international airport in Istanbul after Ataturk Airport on the European side of the city.

According to its website, the airport served around 26 million passengers in the first 11 months of the year.

(FRANCE 24 with AP, AFP, REUTERS)