The capture this week of the Afghan Taliban's military commander was a "significant win" in the efforts to rid the region of extremists, White House spokesman Robert Gibbs said here other day. The Pakistani military earlier Wednesday confirmed that it had Mullah Abdul Ghani Baradar in custody. Baradar heads the Taliban's military wing and is second in command only to the movement's founder Mullah Muhammad Omar. "Obviously the capture of Mullah Baradar is a significant win," Gibbs said, marking the White House's first comments on the arrest. "It's a big success for our mutual efforts in the region." The arrest comes as US, Afghan troops and other NATO allies launched a major military campaign this week against Taliban strongholds in southern Afghanistan. It also represented Pakistan's growing cooperation with efforts to clamp down on the Taliban. There has been a "recognition on the Pakistani military side that extremists in their country posed not simply a threat to us, but an existential threat to them," Gibbs said. According to Pakistani officials, Baradar was captured by Pakistani and US intelligence agents during a raid in Pakistan's southern city of Karachi last week