Lashker-e-Tayiba operative Abdul Karim Tunda, who is admitted at the All India Institute of Medical Sciences in New Delhi, underwent a surgery to implant a pacemaker in his heart on Saturday.

Seventy-year-old Tunda, who was admitted to Safdarjung Hospital Thursday night after he complained of severe chest pain and shifted to AIIMS on Friday afternoon, was detected with complete heart block, hospital sources said. His condition was stated to be stable after the surgery.