Two were killed and four injured in an explosion in a power distribution center in Istanbul's Bahcelievler district on Sunday.

Bombs were discovered in three different places in Istanbul, one of them was exploded and the rest was under police control.

The preliminary police reports stated that the explosion occurred during the maintenance of the unit which is situated inside of the Thracian electric network TEAS.

According to Anatolian news agency, the cause of explosion is still unknown. Crime scene investigation team has been working in the area.

In the meantime, a bomb exploded near another power distribution unit in the Fatih district, no casualties were reported.

Police has detected two other bombs in two Anatolian side districts. One was put under the statue of Mustafa Kemal Ataturk, the founder of modern Turkey, in Maltepe. Another stun grenade was found in a bus stop in Sultangazi.