Afghan President Hamid Karzai has pardoned at least 10 convicted drug traffickers recently, officials say.

Five of those pardoned were arrested in 2007 when they were caught wearing military uniforms and using a police truck for drug smuggling, The Boston Globe reported Friday. An Afghan official told the newspaper the five were from powerful families and one is the son of the politician managing Karzai's campaign for re-election.

"Karzai is pulling out all the stops in his bid to get re-elected,'' said Jake Sherman, now at the Center on International Cooperation at New York University after working in Afghanistan.

U.S. Ambassador Karl Eikenberry asked about drug pardons during a tour of a new justice center built for Afghanistan by the United States. Eikenberry's deputy called the drug pardons "discouraging and unsettling."

Pardoning prisoners is an old tradition in the country to mark religious holidays and other special occasions. But drug traffickers had been barred from pardons, the report said.