By Barbara Starr at the Pentagon and Masoud Popalzai in Afghanistan

Two children have been rearrested in southern Afghanistan for being prospective suicide bombers, the International Security Assistance Force said.

The two "young male" would-be bombers were detained in the past week, the ISAF said in a written statement.

The two kids, both ten years old, were arrested along with three adults, according to the Afghanistan National Directorate of Security (NDS).

Last summer, Afghan President Hamid Karzai pardoned a group of would-be child suicide attackers ranging in age from 8 to 17. Some of the 20 youngsters told Karzai they had been recruited by the Taliban, strapped with vests and ordered to detonate them near foreigners, the president's office said in a statement last August. Militants told the youngsters that the blasts would spare them but kill the foreigners, it said.

The two arrested in Kandahar recently were from that group of pardoned children, according to the NDS statement, and had gone to Quetta, Pakistan to get more training before being sent back to Afghanistan for suicide attacks.

One of the children, from southeastern Afghanistan, said he was told by Mullahs at a madrasa in Pakistan that he would survice the suicide attack and it would not harm him, the NDS statement said. The other child, originally from Pakistan, said he was cheated by armed men and he asked to be pardoned again.

"The cold tactic of using any human being - especially children - to conduct suicide attacks is utterly despicable, and I denounce these tactics," Gen. John Allen, commander of NATO and U.S. forces in Afghanistan, said in the ISAF statement.

The children are "instructed" in suicide bomb vests and indoctrinated, according to a senior ISAF official.

Depending on "how impressionable they are based on their age, they are told they will survive the attack" and "they are told they will be fine," the official explained.

The advantage is no one suspects them, noted the official, and "that plays a big role. The Taliban will do anything to get through the outer perimeter of security."

The official said the Kandahar group tends to target local or provincial officials, sometimes Afghan or coalition forces. The source did not know of any incident in which a child suicide bomber had been used against U.S. forces in Afghanistan.