A huge explosion has rocked a metro station in Turkey's strategic city of Istanbul, Turkish media say.

The blast took place at an overpass close to the Bayrampasa subway station, located on the�European side of the city, the state-run Anadolu Agency reported.

There were conflicting reports on the number of casualties and the cause of the incident.

Atilla Aydiner, the mayor of Istabbul�s Bayrampasa district, noted that five people were wounded in Tuesday�s explosion.

Turkey's Habert�rk television�said that one person had died.

Meanwhile, an unidentified police official told Reuters that the cause of the incident was not clear, adding police investigations into the case were underway.

Istanbul Governor Vasip Sahin said the Turkish officials��are assessing every possibility� concerning the cause of Tuesday�s blast.

Some reports have emerged suggesting that the incident was caused�by a power transformer.

An official for Istanbul's municipality, whose name was not mentioned in reports, also told Reuters that train operations had been halted at the Bayrampasa subway station following the explosion.

Several ambulances were heard rushing to the affected area, which is a residential and industrial neighborhood on the European side of Istanbul, the country�s Dogan news agency reported.

Turkey is on edge with several terrorist attacks targeting the country in recent months. Double explosions on October 10 claimed over 100 lives in the Turkish capital city of Ankara.

The blasts targeted activists who had convened�outside Ankara�s main train station for a peace rally�organized by leftist and pro-Kurdish opposition groups. Ankara has said�that at least 102 people were killed and over 500 wounded in the attacks.

Turkish prosecutors have blamed the assaults on the�Daesh Takfiri�terrorist group.

Turkey has time and again been accused of being one of the main supporters of the militant groups operating in Syria, with reports saying that Ankara actively trains and arms the Takfiri terrorists there and facilitates their safe passage into the conflict-ridden Arab country.

Analysts believe that the activities of Daesh inside Turkey seem to be an inevitable side-effect of support for the militants in Syria.

By Press TV