A suicide bomber killed at least 28 people and wounded dozens on Monday in an explosion at a crowded Shiite mosque in the Afghan capital Kabul, officials said. The attacker entered the Baqir-ul-Olum mosque shortly after midday as worshipers had gathered for a ceremony, the interior ministry said in a statement. Fraidoon Obaidi, chief of the Kabul police Criminal Investigation Department, said at least 28 people were killed and 35 wounded but that total may rise significantly. One survivor told Afghanistan's Ariana Television that around 40 dead and 80 wounded had been taken from the building before rescue services arrived at the scene. "I saw people screaming and covered in blood," he said. Another witness, Sayed Ali, said he had helped carry 30-35 bodies from the mosque and believed another 100 people may be wounded. Bloody sectarian has been relatively rare in Afghanistan, but the attack underlines the deadly new dimension that growing ethnic tension could bring to its decades-long conflict. Already there had been two major recent attacks on Shiite targets in Kabul, both claimed by Daesh (the so-called IS). Last month, at least 14 people were killed when a gunman in police uniform opened fire on worshippers gathered at a shrine for the Ashura festival. In July, more than 80 people were killed in an attack on a demonstration. There was no immediate claim of responsibility for Monday's attack but the Taliban denied any involvement. "We have never attacked mosques as it's not our agenda," said the movement's main spokesman, Zabihullah Mujahid. Any resurgence of sectarian or ethnic violence could threaten the fragile stability of the government headed by President Ashraf Ghani, who described the "vicious attack" as an attempt "to sow seeds of discord." Government Chief Executive Abdullah Abdullah said Afghanistan should not fall victim to "enemy plots that divide us by titles." "This attack targeted innocent civilians — including children — in a holy place. It is a war crime & an act against Islam & humanity," he said in a message on his Twitter account. — Reuters