New Delhi, Jan. 6 :     India today produced ''evidence'' of Islamabad's involvement in the Indian Airlines hijack, releasing names and pictures of the five sky pirates identified as Pakistani nationals and stating in absolute terms that the Inter-Services Intelligence masterminded the operation. Security agencies obtained the hijackers' names and pictures from four Harkat-ul Ansar operatives - two of them Pakistanis, one Indian and the other a Nepalese - who were arrested in Mumbai while negotiations were on to break the standoff at Kandahar. The Centre has handed over part of the case to the CBI. The agency will investigate the Mumbai connection, the involvement of an Indian national in the conspiracy and the alleged security failure to block Amritsar's Raja Sansi airport, where the Airbus stood for nearly 45 minutes before taking off for Lahore, and the murder Rupin Katyal. Home minister L.K. Advani told reporters the breakthrough came with the arrest of four ISI operatives by the Mumbai police between December 29 and 31, following tip-offs from the Intelligence Bureau and the Research and Analysis Wing. ''Pakistan is neck-deep in the dirty game of hijacking,'' Advani said, listing six points to prove Islamabad's hand. The four agents are Harkat members who provided logistical support to the hijackers and extended all assistance at least two months before the operation was carried out from Kathmandu. The agents have been identified as Mohammad Rehan, Mohammad Iqbal, both Pakistani nationals, Yusuf Nepali, a Nepalese, and Abdul Latif, a Mumbai-based Indian. Rehan stays in Karachi and Iqbal is from Multan. The hijackers have been identified as Ibrahim Athar alias Ibrahim Akhtar alias Javed Ahmed Siddiqui from Kaiser Colony in Bahawalpur, Shahid Akhtar Sayed from Gulshan Iqbal, Karachi, Sunny Ahmed Qazi from Defence Area, Karachi, Mistri Zahur Ibrahim from Akhtar Colony, Karachi and Shaqir from Sukkur City, Sindh. Shaqir boarded the plane as Rajesh Gopal Verma. Athar is the younger brother of Harkat general secretary Masood Azhar, who was one of three terrorists released. The passengers and crew of IC 814 have identified the hijackers from the photographs. Security agencies got their first break on the fifth day - December 29 - after Latif received a call on his cellphone from an associate in Pakistan. Latif is believed to have disclosed to the investigators that he was asked to tell a TV correspondent in London to put out a news that the hijackers would blow up the plane if their demands were not met. The conversation was intercepted and the four ISI agents were arrested. Home ministry sources do not rule out the possibility of Latif being a member of the Dawood Ibrahim gang. Though he is from Mumbai, Latif lived for some years in a Gulf country - possibly the United Arab Emirates - from where he was recruited by the ISI. He underwent training at two camps in Pakistan and Afghanistan. According to Advani, Latif was the ''principal accomplice in so far as arranging logistical support'' for the hijackers was concerned. Investigators have been able to piece together Latif's travel details which show that on November 1, 1999, he accompanied Athar - the gang leader - by air from Mumbai to Calcutta. The next leg of the journey was covered by train from Calcutta to New Jalpaiguri from where the two took a bus to Kathmandu. Latif then returned to Mumbai. On December 1, Latif took another hijacker, Shaqir, to Gorakhpur in Uttar Pradesh from where they went to Kathmandu by bus. On December 17, Latif boarded an Indian Airlines flight from Kathmandu to Delhi and returned to Mumbai by train. But there are several loose ends in the unfolding investigation. For instance, the government is yet to establish the hijackers' contacts in Nepal who may have helped them avoid security checks at Kathmandu airport and allowed a suitcase, containing a huge cache of weapons and explosives, to be loaded as checked-in baggage. A home ministry source disclosed that the baggage, which was booked under Verma's name, contained two AK-56 rifles, seven pistols, 11 grenades and 25 kg of explosives. These weapons were displayed by the hijackers at Kandahar. The pirates were carrying Rs 2.5 lakh in cash.