In a special session, the Punjab Assembly on Friday unanimously passed a resolution declaring Sarabjit Singh a national martyr and sought an impartial investigation by an international agency into his "merciless" attack in a Pakistani jail.

Chief Minister Parkash Singh Badal moved the resolution which appealed to the Centre to build up international pressure on Pakistan to ascertain the causes of the brutal attack on Sarabjit in Lahore's Kot Lakhpat Jail.

Paying rich tribute to 49-year-old Sarabjit, the resolution also asked the Centre to "initiate strong and effective diplomatic efforts" to ensure the safety of prisoners belonging to India and those of Indian-origin lodged in prisons of Pakistan and other countries".

Legislators cutting across party lines unanimously passed the resolution moved by the chief minister in the House.

The House also observed a two-minute silence as a mark of respect for the departed soul. Punjab Speaker Charanjit Singh Atwal then adjourned the House till 10.30 am.