Details were sketchy in the immediate aftermath. Police at first said a pair of back-to-back roadside bombs exploded.

Later a police official said first a roadside bomb exploded, then a suicide bomber detonated his device amid the crowd that had gathered. Finally, police concluded that the carnage was the work of a pair of suicide bombers.

All officials spoke on condition of anonymity because they were not authorised to release the information.

No group has claimed responsibility for the blasts, but the Islamic State group has launched near-daily attacks in the capital in recent months.