KABUL, Afghanistan A suicide bomber targeting an American military delegation outside a government office in eastern Afghanistan killed 12 people on Monday, including nine schoolchildren who were walking nearby and two international service members, officials said.
The attack comes as the Taliban and other militants step up bombings and raids on police posts nationwide in a major test of the ability of Afghan soldiers and police to hold their ground without international military forces, who are withdrawing.
Gen. Zelmia Oryakhail, provincial police chief of Paktia province, told CBS News' Mukhtar Ahmad the attacker targeted a joint U.S. military and Afghan Local Police (ALP) patrol. Oryakhail said the bomber on a motorcycle detonated his explosives in Samkani district as American forces passed. He said a local school had just let pupils, who were between 10 and 16 years old, out for the day.
The U.S. military delegation had just attended a security briefing at the district administrative office, said district chief Saleh Mohammad Ahsas, who was in the meeting. He said the bomber appeared to have been waiting for the delegation and struck as the Americans left the compound, and the blast killed people walking nearby including the schoolchildren.
The U.S.-led International Assistance Force - Afghanistan (ISAF) confirmed to CBS News' Ahmad that two troops had been killed in the blast, but their nationalities were withheld, pending notification of family members.
Officials gave conflicting initial reports on the Afghan death toll, but Oryakhail said late Monday that he had accounted for all the bodies - many burned beyond recognition - and the final count was one Afghan policeman and nine dead from the school, along with the two coalition troops.
Seven more Afghan civilians, including two children, were killed Monday in the eastern province of Laghman when their vehicle hit a bomb in the road. A statement from the provincial government said four women and two children had gone with a male driver into the hills to collect firewood. On their way back, their vehicle hit the device, killing everyone inside.
The Afghan army and police are fighting the insurgency this year with little or no help from international forces that have been in Afghanistan since the 2001 U.S.-led invasion to topple the Taliban for sheltering al-Qaida's terrorist leadership after the Sept. 11 attacks on American soil.
As the 2014 withdrawal of most international forces looms, insurgents are intensifying their attacks - using a broad range of tactics from suicide bombings to improvised bombs that are often accidentally detonated by passing vehicles, killing civilians. An assassination campaign against police chiefs and local government officials also has continued.
And in recent weeks, hundreds of Taliban fighters have attempted to take over more territory with attacks on police posts in several parts of the country. Interior Ministry spokesman Sediq Sediqi confirmed that Taliban have launched multiple assaults - assisted, he said, by al-Qaida and the Pakistan-based Haqqani terrorist network - but he insisted Afghan forces were holding their ground.
"The enemy was not able to get control of a single district, not even a police checkpoint," Sediqi said, noting that in the last week alone, security forces have killed 196 Taliban and arrested 117 others.
The escalation in attacks has cost Afghan forces dearly. At least 441 security forces have died in fighting or bombings in the first five months of this year - more than twice the number killed during the same period last year, according to statistics compiled by The Associated Press. Hundreds more have been wounded, losing limbs to bombs and suffering other debilitating injuries.
By contrast, the number of U.S. and other foreign troops killed in action through May 15 this year has dropped dramatically to 58, compared with 153 in the same period last year.
Even as the violence spikes, there are tentative parallel efforts to encourage negotiations.
The Taliban confirmed on Monday that it sent a delegation to Iran for three days of talks, signaling that Tehran could be seeking the role of regional mediator in attempts to end its neighbor's 12-year war.
Spokesman Qari Yousef Ahmadi said in an email that emissaries from the Taliban's political office met with Iranian officials over the weekend. He said a separate group of Taliban clerics attended a religious conference in Tehran.
An Iranian news agency said Saturday that Tehran hosted a Taliban delegation - an unprecedented development, since the Sunni Muslim Taliban have long been enemies of Iran's ruling Shiite clerics.
Ahmadi also said the Taliban's political wing would accept any invitation to conferences, a possible good sign for so-far fruitless efforts to negotiate an end to the Afghan war. Peace talks have sputtered in the past.