At least four people were killed and 38 injured in the explosion on Istanbul’s popular pedestrian thoroughfare Istiklal Avenue, Istanbul Governor Ali Yerlikaya tweeted.

The cause of the explosion, which occurred during the afternoon, was initially not known.

Police and emergency services were at the scene, state broadcaster TRT said.

Footage on social media showed people lying on the ground on the street, a popular shopping destination for tourists in the European part of the Turkish metropole.

Source: dpa/MIA