(CNN) -- A former associate of Osama bin Laden, described by authorities as a "Pakistan-based attack planner," has been arrested in Afghanistan, a spokesman for the NATO-led coalition said Thursday.
The International Security Assistance Force declined to identify the man, saying it was not releasing further information.
"It's part of an ongoing operation," Army Maj. Tim James, spokesman for ISAF's joint command, told CNN by telephone from Afghanistan.
The man was arrested along with two others described as "associates," according to ISAF, during a raid Wednesday in the northern province of Balkh, an insurgent stronghold that borders Uzbekistan.
The arrest follows another a day earlier in the same area of a suspected al Qaeda-linked militant believed responsible for last week's suicide attack at a provincial governor's office that killed an Afghan police commander and wounded a German general, according to an ISAF operational update posted on its website.
The operation comes a month after U.S. commandos killed al Qaeda leader Osama bin Laden in a raid in Abbottabad, Pakistan.
In a statement posted on its website, ISAF released few details about Wednesday's arrest, saying only that it is "suspected he was with bin Laden in Afghanistan in 2001."
He was captured during an overnight operation after he was tracked to a compound in Nahr-e Shahi, the statement said.