Kabul, Afghanistan (CNN) -- A suicide bomb in Afghanistan's capital killed at least a dozen civilians and five U.S. troops on Tuesday -- a bloody strike claimed by the Taliban and deplored by the NATO coalition. The blast, which occurred on a busy road near a NATO-led military convoy and a registration center for the Afghan Army, rocked an area close to government buildings fortified with security.
Officials were still trying to sort out the casualty numbers. Local medical officials said at least 12 civilians were killed and 48 others were injured. The British Foreign Office put the civilian death toll at 19.
Along with the five American troops, a Canadian service member died, Canada's forces confirmed.
A spokesman for NATO's International Security Assistance Force confirmed that five U.S. military vehicles were destroyed along with 13 civilian vehicles. One of the civilian vehicles was a bus filled with people.
Hours after the explosion, a nearby field was littered with charred body parts, some thrown hundreds of meters from the blast site.
Zabiullah Mujahid, a Taliban spokesman, confirmed the operation and said the attacker was able to "destroy five foreign vehicles and damage one more."
Calling the attack a "deplorable act of violence," the U.S. Embassy said the strike demonstrates the Taliban's "callous disregard for the well being of the Afghan people."
British Foreign Minister Alistair Burt condemned the strike and said the British and international commitment "to support the Afghan government and people to work for a political solution through the peace jirga at the end of this month will not be shaken."
The jirga is an assembly of tribal elders. Afghan President Hamid Karzai wants the elders to support a reintegration plan for Taliban members who renounce violence and lay down their arms.
Brig. Gen. Josef Blotz, an ISAF spokesman, called Tuesday's attack "desperate brutality and aggression" and said it reflects "the pessimism of an enemy who seek to kill the innocent and to stop the progress necessary for a better Afghanistan."