All the Pakistani prisoners were handed over to Pakistan at the joint check post of international Indo-Pak Attari border, an official said.
They crossed over to Pakistan through the land transit route of Attari border on the basis of 'Emergency Travel Certificate' issued by the Pakistan High Commission based at New Delhi, he said.
Out of nine prisoners, five were fishermen who had slipped to India during fishing in the Arabian sea and subsequently arrested for illegal fishing on Indian side. All the fishermen were resident of Karachi province of Pakistan, said the official.
However, four other Pakistani prisoners were arrested in inadvertent border crossing, he said. All the Pakistani prisoners spent nearly two years in prison in Indian jails.