"We told the counsel of Mr Lakhvi that we cannot release him on the Islamabad High Court order received through fax," said an official at the Adiala Jail in Rawalpindi.
He said, "We told him (Lakhvi's counsel) to bring the certified copy of the court's order".
The Islamabad High Court today suspended the detention order of LeT operations commander Lakhvi, 54, and ordered his immediate release, drawing India's ire.
Lakhvi, along with six others, is the prime accused in the case of the 2008 Mumbai terror attack that killed 166 people.