Delhi Police arrested Balwinder Singh, 24, from Nawashahar in Punjab Tuesday morning. He disclosed the names of three others who were allegedly involved in the May 22 blasts at Liberty and Satyam cinemas.
One of the three men identified by Balwinder and arrested from Madipur in west Delhi later in the day was said to be Jagannath, an associated of Balwinder but apparently not a Babbar Khalsa member.
The others named by Balwinder are Jaspal alias Raju, another Babbar Khalsa activists, and Vikas who, like Jagannath, was described as an associate. Vikas and Jagannath are Hindus, and a police officer said they were "lured into it".
Balwinder and Jaspal were allegedly recruited in December 2004 by Babar Khalsa International, a terrorist outfit reportedly supported by Pakistan and some non-resident Indian Sikh groups to propagate the ideology of Khalistan - a separate Sikh homeland.
Balwinder and Jaspal had travelled to Bangkok April 22, where a man identified only as Shahid met them. They returned to New Delhi May 13.
"After meticulously going through available evidence we concluded that there were three or more people involved in the blasts," Delhi Police Commissioner K.K. Paul told a news conference.
"A Special Cell team was sent to Punjab after receiving information about some suspects. The team is camping in Punjab. Jaspal and Vikas are at large and will soon be in our net," Paul said.
Balwinder confessed to the crime and was to be brought to New Delhi Tuesday evening.
According to Paul, the entire scene of the crime was recreated with the help of witnesses, some of the injured and other units of Delhi Police.
The four suspects conducted a reconnaissance on the two cinemas May 21.
On the day of the blasts, the four started off together in a Tata Seirra vehicle that had specially designed cavities to hide explosives from the Inderpuri area in southwest Delhi.
Balwinder, Vikas and Jaspal entered Liberty where Japsal prepared the bomb inside the toilet and left the theatre before the interval. Balwinder and Vikas left after the interval.
While the explosives were taken in as separate pieces - in four sheets wrapped in polythene - to avoid detection, the detonators and wires were carried inside their underwear.
Jaspal and Jagannath then reached Satyam multiplex and placed a bomb in the toilet there.
While Commissioner Paul did not rule out the possibility of the attacks being related to the Sunny Deol starrer "Jo bole So Nihaal" that were being screened at both cinemas, he denied there was specific information to establish such a connection.
"They wanted to send some kind of a message through the blasts. However, though there seems to be a connection between the movie and the blasts, nothing specific has been established as of now," Paul said.
"Detailed interrogation of the arrested men and the arrests of their absconding associates will throw up further details of the entire operation."
The search of Jagannath's house in Uttam Nagar in west Delh led to the recovery of a kg of RDX explosives, two kg of gold and Rs.294,000 in cash.
Some Sikh groups had demanded a ban on "Jo Bole So Nihaal", saying its title and some of its scenes had offended their religious sentiments.
The movie was pulled out of many theatres across India after the blasts in New Delhi.