Suicide bombers have struck two mosques in Afghanistan during Friday prayers, a Shiite mosque in Kabul and a Sunni mosque in western Ghor province, killing at least 72 people.
The deaths come at the end of a particularly deadly week for the troubled nation.
The Afghan President issued a statement condemning both attacks and saying the country's security forces would step up the fight to "eliminate the terrorists who target Afghans of all religions and tribes".
Photo taken on Oct. 20, 2017 shows the scene inside a mosque after an attack in Kabul, capital of Afghanistan. (Photo: Xinhua/Barcroft Images)
In the attack in Kabul, a suicide bomber walked into the Imam Zaman Mosque, a Shiite mosque in the western Dashte-e-Barchi neighbourhood, where he detonated his explosives vest, Major General Alimast Momand said.
Fatalities from the attack had risen to 39 dead, with 41 wounded, Afghanistan's Interior Ministry said.
The ministry's press office said in a statement it was investigating the attack at the Imam Zaman Mosque.
It also said the assailant blew himself up as worshippers began their prayers.
The Islamic State (IS) group later claimed responsibility for the attack, but did not provide evidence.
The suicide bombing in Ghor province struck a Sunni mosque — also during Friday prayers — and killed 33 people, including a warlord who was apparently the target of the attack, said spokesman for the provincial chief of police Mohammad Iqbal Nizami.
No group immediately claimed responsibility for the attack, the latest in a devastating week that saw Taliban attacks kill scores across the country.
In the Kabul attack, witness Ali Mohammad said the mosque was packed with worshippers, both men and women praying at the height of the Muslim week.
On Tuesday, the Taliban unleashed a wave of attacks across Afghanistan, targeting police compounds and government facilities with suicide bombers, and killing at least 74 people, officials said.
The explosion was so strong that it shattered windows on nearby buildings, he said.
Local residents who rushed to the scene to help the victims were overcome with anger and started chanting "death to ISIS", a reference to the IS group which has staged similar attacks on Shiite mosques in recent months.
Abdul Hussain Hussainzada, a Shiite community leader, said they were sure that Afghanistan's IS affiliate was behind the attack.
"Our community is very worried," Mr Hussainzada said.
Mr Hussainzada, the spiritual head of Afghanistan's ethnic Hazaras, said the suicide bomber had positioned himself at the front of the prayer hall, standing with other men in the first of dozens of rows of worshippers before exploding his device.
Brutal week sees more than 70 killed
The attack on the Sunni mosque in Ghor province took place in the Do Laina district, according to Mr Nizami.
Mr Nizami said the target apparently was a local commander, Abdul Ahed, a former warlord who has sided with the Government. Seven of his bodyguards were also killed in the bombing.
In his statement, President Ashraf Ghani said the day's attacks show "the terrorists have once again staged bloody attacks, but they will not achieve their evil purposes and sow discord among the Afghans".
It has been a brutal week in Afghanistan, with more than 70 killed, mostly policemen and Afghan soldiers but also civilians as militant attacks have surged.
The Taliban have taken responsibility for the earlier assaults this week that struck on security installations in the east and west of the country.
Overnight on Wednesday and into Thursday, the Taliban killed at least 58 Afghan security forces in attacks that included an assault that nearly wiped out an army camp in southern Kandahar province.
On Tuesday, the Taliban unleashed a wave of attacks across Afghanistan, targeting police compounds and government facilities with suicide bombers, and killing at least 74 people, officials said.
Afghan forces have struggled to combat a resurgent Taliban since US and NATO forces formally concluded their combat mission at the end of 2014, switching to a counterterrorism and support role.