In pictures: Istanbul blasts

At least 15 people have been killed and around 150 injured by two explosions in the Turkish city of Istanbul, its governor has said.

The first blast happened on a busy pedestrian street of the Gungoren district. The second, much larger blast came as crowds gathered.

Shortly after the explosions, television footage showed the injured lying on the street and others being carried in blankets.

Istanbul governor Muammer Guler - giving details of the number of those killed - called it a "terror attack", without elaborating. So far there has been no indication of who was responsible.

President Abdullah Gul said the attack showed "the ruthlessness of terrorism and its goal to engage in savagery".

Police said they believed the blasts were not suicide bombings, but activated either remotely or by means of a timer.