A pipe bomb explosion near a train station in Istanbul has left five people injured, the district mayor says.

The blast near the Bayrampasa metro station came at the height of the evening rush hour, mayor Atilla Aydiner told A Haber television.

Bayrampasa is a residential and industrial area on the European side of Istanbul.

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Turkey has been on high alert since more than 100 people were killed by two suicide bombers in the capital Ankara in October, three months after a similar attack at a town near the Syrian border in July left 33 dead.

Grainy CCTV footage showed a large flash of light on the overpass followed by what appeared to be burning embers showering to the ground as cars drove below.

Photographs on social media showed what appeared to be dozens of people walking alongside overground train tracks after trains had been halted.

Although Istanbul’s metro is largely underground, it runs above ground in some places, including around Bayrampasa.

Turkey, a NATO member, has carried out air strikes against the Islamist insurgents in neighbouring Syria as part of the US-led coalition fighting the jihadist movement.

It also faces security threats from the outlawed Kurdistan Workers Party (PKK), whose militants often attack police and security in Turkey’s mainly Kurdish south-east, and the far-left Revolutionary People’s Liberation Army-Front (DHKP-C).

The DHKP-C, which is considered a terrorist organisation by the United States and Ankara, said that one of its members was involved in an attack on the US consulate in August.

Watch the footage below: