The three, including two elderly women, died after the driver of a bus in Istanbul’s Bagcilar district reversed his vehicle after fire bombs were thrown through the windows by a group of unidentified assailants that police said were linked to the terrorist organisation the PKK.

Following the attack, a group gathered to chant slogans in support of the outlawed PKK, which has staged a more than 20 year long separatist campaign against the Turkish state.

The bus came to rest on the pavement after the attack and was completely burnt out.

There has been an upsurge of violence across Turkey in the past week, following the deaths of 14 PKK militants in clashes with security forces in the south east in late March.