NEW DELHI: Lashker-e-Taiba (LeT) operative Abdul Karim Tunda , who is admitted at AIIMS here, underwent a surgery on Sunday to implant a pacemaker in his heart.

70-year-old Tunda, who was admitted to Safdarjung Hospital on Thursday night after he complained of severe chest pain and shifted to All India Institute of Medical Sciences on Friday afternoon, was detected with complete heart block, hospital sources said.

His condition was stated to be stable after the surgery.

"Tunda was taken to the cath lab at around 2.45pm on Saturday from the cardiac care unit following which the doctors implanted a pacemaker in his heart," they said.

He underwent the procedure in the supervision of cardio consultants Dr Nitish Naik and Dr Gautam Sharma.

A pacemaker is a small device implanted in the patient to control heartbeat.

Complete heart block occurs when the electrical signal can't pass normally from the atria, the heart's upper chambers, to the ventricles or lower chambers.

A heavy contingent of armed police guards were deployed outside the ward where Tunda is being treated.

Earlier during the day, a magistrate visited Tunda in hospital and remanded him in judicial custody till September 7.

Tunda, who was arrested from the India-Nepal border last Friday, is a close assistant of underworld don Dawood Ibrahim and one of 20 terrorists India had asked the Pakistan government to hand over after the 26/11 Mumbai terror attacks. He is suspected to be involved in 40 bombings in the country and is the first in the list to be arrested.

According to Delhi Police, he is wanted for his role in 1993 Mumbai serial train blasts, Delhi bomb blasts of 1997-98 and serial bombings in the state of UP and also at Panipat, Sonepat, Ludhiana and Hyderabad.