The attack tore through a busy pedestrian thoroughfare popular with tourists. It was unclear who carried it out.

Video

Video player loading

Video showing people fleeing after an explosion that killed several people and wounded dozens of others near Taksim Square, one of the city’s busiest areas.CreditCredit…Kemal Aslan/Rueters

ISTANBUL — An explosion shook a bustling pedestrian thoroughfare in central Istanbul on Sunday, killing at least six people and leaving at least 53 wounded, President Recep Tayyip Erdogan said.

Mr. Erdogan attributed the blast to a “bomb attack” and said those who carried it out would be punished, without accusing any specific group of being behind it.

The blast hit Istiklal Avenue, a short walk from Taksim Square and one of the city’s busiest areas for shopping, tourism and transit. A soccer game scheduled for later Sunday evening nearby may have brought even more people than usual to the area.

Videos shared on social media showed an orange fireball rising from the street and crowds of people panicking and rushing to flee the area. Other videos from the scene showed a number of badly wounded people on the ground, some of them covered in blood and not moving.

A TV reporter at the scene said he had seen at least five people wounded but walking, and at least four others lying on the ground.

Ambulances and fire trucks raced to the area, and a helicopter was spotted hovering overhead. The police cordoned off the area. Some stores nearby had closed their shutters immediately after the blast, but then reopened for people seeking shelter.

Carlotta Gall contributed reporting.