A suicide attack in a public bathhouse in southern Afghanistan has killed at least 16 civilians and a police commander, officials have said.
More than 20 others were injured in the blast, which occurred on Friday in the town of Spin Boldak in Kandahar province, on the border with Pakistan.
"A suicide bomber blew up explosives strapped to his chest at a public bath in Spin Boldak," General Abdul Razaq, a border police official, said.
Zalmai Ayoubi, a spokesman for the governor, said the target of the attack had been a border police commander who was inside the bathhouse at the time of the attack.
"This brutal and inhumane act was the work of the enemies of Islam and humanity," he said.
Mujebullah, a local shopkeeper whose cousin was wounded in the attack, told the AFP news agency that the baths were in a crowded market and used by people to wash before attending prayers.
"The public baths were destroyed. Lots of dead bodies were picked out of the rubble at the beginning and afterwards," he was quoted as saying.
"Different people were killed in this explosion - old people, even children."
A Taliban spokesman said the group had carried out the attack and confirmed it had targeted the second-in-command of a border patrol force in the area. It was not immediately clear if he was the police officer killed in the blast.
The south has traditionally been the Taliban's stronghold but suicide attacks targeting civilians in public places are relatively rare.
Hamid Karzai, the Afghan president, called the bombing "brutal".
"Those behind this attack should know once again that the blood of the Muslim people has been spilled. It will not have any other result," he said in a statement.
The US embassy and NATO in Afghanistan also issued statements condemning the bombing, with the US describing it as a "callous terrorist act".
Also on Friday, NATO announced that three of its service members were killed in two separate roadside bombings in southern Afghanistan.
The attacks come after the end of the bloodiest year of a war that has now dragged on for more than nine years.
The United Nations has said 2,412 civilians were killed and 3,803 wounded between January and October last year, a 20 per cent increase on 2009.
A record 711 foreign troops were killed in 2010, according to monitoring website www.iCasualties.com ,
compared to 521 for 2009.
Afghan security forces have been hit even harder than foreign troops. A total of 1,292 Afghan police and 821 Afghan soldiers were killed in 2010, according to the Afghan government.