Five people were injured today (December 1, 2015) when a pipe bomb exploded on an overpass near an Istanbul metro station, halting some train operations and heightening security fears in Europe's biggest city, according to the Reuters website.
Turkey has been on high alert since more than 100 people were killed by two suicide bombers in its capital of Ankara in October.
Today's blast near the Bayrampasa metro station came at the height of the evening rush hour, district Mayor Atila Aydiner told A Haber television. Bayrampasa is a residential and industrial area on the European side of Istanbul.
Today's explosion was much smaller than the one in Ankara, which is believed to have been carried out by Islamic State (IS) radicals.