KABUL (Reuters) -A blast tore through a Sunni mosque during Friday prayers in the northern Afghan city of Kunduz, killing 33 people and wounding dozens more, officials said.

       Zabihullah Mujahid, spokesman for the Taliban administration, in a Tweet confirmed the death toll and said 43 people had also been wounded.

       "The perpetrators of these incidents are...evil elements and serious efforts are being made to arrest and punish them," he said.

       It was not clear who was behind the explosion that the local commander said hit the mosque during Friday prayers.

       Several blasts claimed by Islamic State hit the northern cities of Kunduz and Mazar-i-Sharif on Thursday. One of them, at a mosque and another days earlier at a school in western Kabul, targeted the Shi'ite minority.

       Afghanistan's Taliban rulers say they have secured the country since taking power in August, but international officials and analysts say the risk of a resurgence in militancy remains.

       (Reporting by Kabul Newsroom; Writing by Charlotte GreenfieldEditing by Raissa Kasolowsky and Alistair Bell)