Ail Haider Gilani was kidnapped May 2 during an election campaign in Multan city.
Abu Yazeed, a spokesperson for the outfit calling itself Al-Mansooreen Brigade, said Ali Haider Gilani was in their custody and safe.
The group would soon release a video of Ali Haider Gillani shortly after Eid and apprise about their demands, he added.
Photos: Shraddha Kapoor, Kim Sharma at 'Haseena Parkar' screening
Mumbai to Goa train: First look at the glass-top Vistadome coach
Shuttler Ashwini Ponnappa keeps it short and sexy on social media
Photos: Narendra Modi, others at Marshal Arjan Singh's funeral
Photos: Sussanne Khan and Nimrat Kaur spotted at a spa in Juhu