Islamabad, Pakistan (CNN) -- Pakistan has released Mullah Abdul Ghani Baradar, one of the founding members of the Afghan Taliban, foreign ministry spokesman Aizaz Chaudhry told CNN on Saturday.
Baradar, who had been held in a secret location, used to be the organization's second-in-command, after Mullah Mohammed Omar himself.
"Afghan President's office welcomes the release of Mullah Baradar from jail in Pakistan," Aimal Faizi, spokesman for Afghan President Hamid Karzai, said on Twitter.
Pakistani officials this month announced their plans to release Baradar "in principle."
Baradar was captured in 2010 in Karachi, Pakistan's largest city, which is known to be a haven for many militants from across the country and its bordering regions.
This is the second peaceful overture by the newly elected Pakistani government to neighboring Afghanistan. On September 7, it released seven Taliban figures to facilitate the peace process.
That release came just two weeks after Afghan President Hamid Karzai visited the capital of Islamabad and stressed Pakistan's assistance in a path to peace. Karzai has long pushed for Baradar's release; his government was suspected to be in secret talks with the wanted militant when he was captured.
The Afghan Taliban said this month that it welcomed the Pakistani government's plan to release Baradar and that it was assessing the wider situation.
"Pakistan's move to release seven top commanders at the weekend and plans to release Mullah Baradar is a positive development. We'll respond as things shape up over the coming days and weeks," spokesman Zabiullah Muajhid told CNN at the time.
A spokeswoman for the U.S. Embassy in Islamabad, Meghan Gregonis, had said Pakistan and Afghanistan should have proper coordination to "ensure releases are effected in a responsible manner."
Baradar had been under United Nations sanctions since February 2001, with his assets frozen and travel banned. The U.N. had forbidden selling weapons to him.