The death toll from Friday's mosque attack in Kabul has risen to 28, while more than 50 were injured, including women and children.
The figure was confirmed to dpa by Mohammad Ismail Kawoosi, a spokesman for the Ministry of Public Health.
Earlier officials have spoken of 25 dead and 40 injured.
Insurgents stormed a Shiite mosque in Kabul during Friday prayers when the mosque was full.
Two people were involved in the attack, Basir Mujahid, a spokesman for Kabul police, told dpa, adding that it was started with a suicide blast at the gate of the Imam Zaman Shiite mosque in the Khair Khana area of central Kabul.
According to Mujahid, the second attacker was gunned down by Afghan security forces during a five-hour long operation.
The Islamic State extremist group claimed responsibility for the explosions, saying that two of its members carried out the attack,
according to the Amaq agency, with which the group is affiliated. Beside others, the Afghan presidential palace, the United Nations Assistance Mission in Afghanistan (UNAMA), Human Rights Watch and NATO have strongly condemned the mosque attack.
At the beginning of August, at least 50 people were killed and 80 injured when insurgents attacked a Shiite mosque in the capital city of Afghanistan's western Herat province.
The last attack on a Shiite mosque in Kabul, in June, left at least six dead.
Islamic State, which considers Shiite Muslims to be heretics, claimed responsibility for both attacks.
A security guard keeps watch as Afghan mourners and relatives pray in front of the coffin of one of the 28 victims of a suicide attack, on a Shiite mosque a day earlier, in Kabul. AFP