"The Punjab government today (Thursday) entrusted the investigation to the CBI to nab the perpetrators and their anti-national co-conspirators residing abroad," a government spokesperson said.
"A decision to this effect was taken in view of the need for a strong inter-agency approach to bring the accused to book," he said.
The recommendation was formally made by Director General of Police (DGP) Suresh Arora on Wednesday.
The police had earlier set up a special investigation team (SIT) to probe the attack on Gagneja.
"During the course of investigation (by the SIT) it was revealed that the attack could be the handiwork of anti-national elements that were likely to have a nexus with extremist elements living abroad," the spokesperson said.
"The nature of the targeting reflected the underlying motive of the perpetrators to disturb peace in Punjab. The act also had ramifications at the national and international level," he said.
Gagneja, senior vice president of the Punjab unit of Rashtriya Swayamsevak Sangh, was shot thrice in the abdomen from a close range by two young men on a motor-cycle in a busy area in Jalandhar on August 6.
The critically injured Gagneja was shifted to the Hero DMC Heart Institute in Ludhiana from a private hospital in Jalandhar.
The Punjab Police could not make any arrests or reveal the conspiracy behind the attack.
The police also announced a reward of Rs 10 lakh and a job to anyone providing information on the shooters. However, it has drawn a blank so far.
The Jalandhar police had got hold of CCTV video of different places in which two youths, wearing 'patkas' (a religious headgear worn by young Sikh boys) and with their faces covered with cloth, were seen moving around on a motorcycle.
The footage also indicated the suspected assailants had trailed Gagneja, who retired from the army as a Brigadier in 2003, for some time before firing at him at the busy Jyoti Chowk area in the heart of Jalandhar, 155 km from here.
The Punjab RSS and the state BJP leadership have taken the attack on Gagneja very seriously.
The Shiromani Akali Dal and the Bharatiya Janata Party have an alliance government in Punjab since 2007. The state goes for assembly polls in February next year.
