A three-member bench of the apec court headed by Justice Asif Saeed Khosa and comprising Justice Dost Muhammad heard the case.
During the proceedings, Justice Asif Saeed Khosa remarked that the prosecution failed to prove their case.
The accused including Intekhab Abbasi, Zafar Ali and Muhammad Kabeer were earlier sentenced to death by the trial court. High Court had converted their punishment to life-imprisonment.
The three were also accused of having contacts with Tehreek-e-Taliban Pakistan.