The Punjab police is learnt to have detained a man from Tarn Taran district in connection with the explosion at the intelligence wing headquarters in Mohali, sources said on Wednesday.
Nishan Singh, a resident of Kulla village in Tarn Taran district, will be questioned for his alleged role in the Mohali explosion incident, said sources.
Singh is already facing several criminal cases including one related to ’attempt to murder' and another under the Narcotic Drugs and Psychotropic Substances Act.
The Punjab police have already rounded up several suspects for questioning.
In an audacious attack on Monday, a rocket-propelled grenade was fired at the third floor of the highly-guarded building in Mohali's Sector 77 at 7.45 pm, which sent the state in a high alert mode.
On Wednesday, a CCTV footage of the RPG attack also emerged.
In the video, a car was seen moving on the road in front of the building of the intelligence headquarters. Suddenly, there was a flash of light, suggesting that the RPG was fired from that moving car.
The police on Tuesday had said that it had recovered the launcher used in the attack.
The Mohali police had on Monday termed the explosion at the headquarters as ”minor”.
In his statement after the attack, Punjab Chief Minister Bhagwant Mann had promised strictest punishment to those trying to spoil the state's atmosphere.
Mann, who had held a meeting with the director general of police and other senior officials on Tuesday, had said that nobody would be allowed to disturb the peaceful atmosphere of Punjab.
He had said the elements trying to foment unrest in the state will not be allowed to succeed.
A case under the relevant sections of the Indian Penal Code, the Unlawful Activities (Prevention) Act, and the Explosives Act was lodged at Mohali's Sohana police station after the incident.
DGP K Bhawra had earlier said that a projectile had hit the building and the explosive used in it seems to be TNT (trinitrotoluene).
The police are suspecting the involvement of gangster-turned-terrorist Harvinder Singh Rinda, who is believed to be in Pakistan, in the incident.
Rinda has been taking the help of local gangsters to carry out anti-national activities here, police sources said.
His name came up when a terror plot was foiled recently with the arrest of four suspected Pakistan-linked terrorists in Haryana's Karnal.
Rinda's involvement was also detected in a hand-grenade attack at the crime investigation agency office in Nawanshahr last month.