KABUL, Afghanistan — A suicide bomber sneaked into a police dining hall in central Afghanistan at lunchtime Friday and blew himself up, killing 12, while a border police officer and a civilian were killed in a separate suicide attack in the south, authorities said.

Investigators are still trying to determine how the suicide bomber passed two checkpoints to enter the crowded hall at about 12:30 p.m., said Uruzgan provincial police spokesman Fared Ayil. He said authorities had not ruled out that the attacker may have been a police officer himself or wearing a police uniform.

The bomber entered the dining hall and detonated a suicide vest just inside the door, he said. The dining hall was on a base in Tarin Kowt, Uruzgan's capital, used by police assigned to secure the main highway to neighboring Kandahar.

Afghan media reported 10 of the 12 victims were Afghan national police officers. Uruzgan provincial government spokesman Abdullah Himmat, however, would only say that the dead were "primarily police." Five other people were wounded in the explosion.

Part of the problem identifying the victims is that three or four bodies were so badly torn up by the blast that authorities could not immediately determine if they were police or civilians, Ayil said. Relatives of police officers had been present in the dining hall at the time of the attack, he said.

This year has seen violence levels comparable to the worst in nearly 12 years of war in Afghanistan. Though the Taliban have recently indicated they would be open to beginning peace talks, they have also said they will not give up their attacks.

In an email statement sent out Friday, Taliban spokesman Zabiullah Mujahid vowed to continue jihad, or holy war, through the Muslim holy month of Ramadan, which begins next week.

"Ramadan is a holy month and jihad is a holy cause," he said. "The mujahedeen will continue their tactics and attacks against the enemy."

In the southern province of Kandahar, a suicide bomber blew himself up at a border checkpoint entering Afghanistan from Pakistan, killing at least two people and wounding eight others.

Kandahar provincial government spokesman Javeed Faisal said the attacker detonated his explosives at midmorning at the gates of the Spin Boldak crossing into Afghanistan, which is used by thousands of people every day.

In addition to the suicide bomber, the blast killed one border police officer and wounded one, and killed one civilian and wounded seven others.

Border police say the officer killed was the checkpoint commander, and they assume he was the target.

There was no immediate claim of responsibility. Such attacks are usually the work of Islamic militants.

In another incident on Friday in Uruzgan, Himmat, the government spokesman, said a boy and a girl were killed by a roadside bomb on their way home around midday.


Amir Shah contributed to this story; Khan reported from Kandahar, Afghanistan