A suicide attack on a Shi'ite Muslim shrine in Kabul on Tuesday killed up to 20 people and injured five, a senior police official said, adding that the death toll was expected to rise.

Hundreds of people had gathered at the shrine to celebrate the festival of Ashura, which marks the martyrdom of the Prophet Mohammad's grandson Hussein in the battle of Karbala in Iraq in the year 680.

(Reporting by Mirwais Harooni, writing by Jan Harvey)