A suicide bomber has attacked a mosque in Afghanistan as people gathered to celebrate the Eid al Adha holiday.
Between 36 and 41 people, including at least five children, died in the attack in the town of Maymana, capital of northern Faryab province.
Top provincial officials, including the governor and the police chief, were inside the building when the bomber set off his explosives outside the packed Eid Gah mosque.
The officials were not hurt, but the dead included police officers, soldiers, intelligence agents and civilians. Dozens were wounded.
There was no immediate claim of responsibility, but suicide bombings are a favourite weapon of Taliban Islamists trying to topple the Western-backed government of President Hamid Karzai.
One eyewitness, Sayed Moqeed, described the bomber as appearing to be in his early teens.
"Suddenly I heard a very big explosion," he said. "Everywhere were pieces of bodies, hands and limbs. The suicide attacker was in police uniform, he looked to be around 14 or 15 years old."
Deputy Governor Abdul Satar Barez said: "The targets of the bomber were all the officials inside the mosque."
It appeared to be the deadliest suicide attack in recent months.
On September 4, 25 civilians were killed and more than 35 wounded in Nanghar province, and on September 1, 12 people were killed and 47 wounded in a suicide attack in Wardak province.
Mr Karzai strongly condemned the attack, saying that those who carried it out were "enemies of Islam and humanity."
The attack came as Mr Karzai was urging Taliban insurgents "to stop killing other Afghans".
In his Eid al Adha message to the nation, Mr Karzai called on the insurgents to "stop the destruction of our mosques, hospitals and schools".
The United Nations says that Taliban attacks account for the vast majority of civilian casualties in the 11-year war. The insurgents routinely deny that they are responsible for attacks on civilians, saying they target only foreign troops or members of the Afghan security forces.