Gunman opens fire on Istanbul diners in 'revenge attack'

A Turkish gunman has killed at least one person and injured many others after opening fire at an Istanbul restaurant on Monday.

The shooting took place at an outlet of the Big Chef restaurant chain in the city's Byekoz neighbourhood.

According to reports, the assailant challenged a diner, accusing them of murdering his father 12 years ago.

Witnesses said he then fired at the customer, who later died from his wounds.

While the fate of the gunman remains unclear, reports say that those injured in the attack were taken to "several hospitals" around the city.

This latest attack comes as Istanbul remains on high-alert following the killing of dozens of revellers at one of the city's most exclusive nightclubs on New Year's Eve. 

Responsibility for the shooting was claimed by Islamic State group, who also attacked the city's airport last year.