Though no group has claimed responsibility for the abduction, Gilani and other members of his family told The Express Tribune that Ali Haider had been receiving "death and kidnapping threats" from the LeJ and Sipah-e-Sahaba.
Ali Haider, 27, was kidnapped Thursday while campaigning for the May 11 polls in his hometown of Multan, often considered a stronghold of the Gilani family.
The gunmen shot and killed Ali Haider's personal secretary and a bodyguard when they resisted.
Police arrested five suspects in Multan and officials claimed two of them had "important information" about the kidnapping.
While there was no official word on the interrogation of the suspects, the Tribune quoted its sources as saying that Ali Haider had been taken by his abductors to Kabeerwaala, considered a stronghold of the LeJ.
The banned Tehrik-e-Taliban Pakistan refused to comment on the abduction.
"I do not want to comment (on the incident). We do not know as to who has kidnapped him, and why and how he was kidnapped," said Taliban spokesman Ihsanullah Ihsan.
Sources in Punjab Police told PTI yesterday that they believed Ali Haider was kidnapped by a faction of the Punjabi Taliban based in Mian Chanu, 80 km from Multan district.
The Punjabi Taliban largely comprises members of the LeJ, which also has links with al-Qaeda.
The LeJ has been linked to a series of high-profile terrorist acts, including the 2009 attack on the Sri Lankan cricket team in Lahore and two deadly bomb attacks in Quetta earlier this year that killed nearly 200 people, a majority of them Hazara Shias.
Image: Ali Haidar Gilani
Photograph: Reuters
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