Bomb blast on Turkish train

At least four people have been wounded by a blast on board a train at a station in Turkey's largest city, Istanbul.

Police said the explosion was caused by a time-controlled fragmentation device which had been placed in a carriage.

They said they did not know who carried out the attack, but the Turkish Interior Ministry had earlier warned police forces throughout the country to be extra vigilant.

It said there was an increased risk of attacks by Islamic militants during New Year festivities, which this year coincide with the start of Ramadan.

From the newsroom of the BBC World Service