MIAMI- US Defense Secretary Jim Mattis said on Thursday he was hopeful that the freeing of a kidnapped US-Canadian couple and their three children in Pakistan was a harbinger for closer cooperation in the future. 'This is a very positive moment and the Pakistan Army performed well,' Mattis told reporters on board a military plane, adding he hoped this would be 'a harbinger for the future.' 'We intend to work with Pakistan in a collaborative way in the future to stop terrorism and that includes kidnapping,' Mattis added. He declined to comment on any specifics on how the hostages were freed.