ANKARA -- Two people were killed and four others injured on Friday when an air tank exploded at the metro construction site in western Turkey, the semi-official Anatolia news agency reported.

The explosion took place in Izmir city of Izmir province, said Anatolia, adding reporters are not being allowed to enter the site of the explosion.

Adnan Oguz Akyarli, a senior official of Izmir city, said Izmir mayor Aziz Kocaoglu had went to the explosion site immediately.

Walls of surrounding buildings cracked and glasses were broken due to the explosion.