Hamza (who also goes under the name of Kanchan and Hilal) is alleged to be involved in all three terror strikes in Hyderabad, including the Mecca Masjid (May 18, 2007) and the STF attack (October 12, 2005), and is said to be a close associate of the mastermind, Pakistan-based HUJI commander Shahid Bilal.

Hamza’s name also figured in several interrogation statements and investigations into the strike at Varanasi’s Sankatmochan temple.

As of now, there has been complete silence from Dhaka with no confirmation of the arrest from Bangladesh authorities. There have been indications over the past few months that the current regime in Bangladesh is keen to assist India by acting on specific intelligence inputs regarding militant leaders or groups. The Indo-Bangla Home Secretary-level talks here last month also saw some progress in this direction with the two countries agreeing to put a joint mechanism in place.

Union Home Secretary Madhukar Gupta said the government was aware of reports of the arrest but was verifying them “through our agencies”.

Sources said that once CBI approaches Dhaka through Interpol, Bangla authorities would have to inform Interpol if they had arrested Hamza or were aware of his whereabouts.

Investigations, meanwhile, are still on to establish if Hamza was directly involved in the process of making the bomb or triggering the twin blasts. Hamza, who belongs to Rajshahi and is believed to have been working closely with Bilal, is said to be well-versed in explosives.

Recruited into HUJI by Rasool Khan Party after the Gujarat riots, Bilal set up networks in Hyderabad with the help of Asad Yazdani. A resident of Hyderabad’s Toli Chowki area, Yazdani operated under the alias Naved Gul and was allegedly involved in several terrorist strikes and the Pandya murder in which Hamza’s name figured.

Hamza was named as having allegedly helped Hyderabad men Yazdani and Mohammed Abdul Shahed in transporting and looking after terror trainees from Hyderabad, police sources said. His name was also mentioned by Mohammed Ibrahim, Abdul Sattar, Mohammed Abdul Kaleem and Khaja, all sent from Hyderabad, on the orders of Bilal, in early 2005, to Yazdani in Bangladesh and subsequently to Pakistan for arms and explosives training.

Yazdani and Khaja were killed in March 2006 in an alleged police encounter in New Delhi. The others Ibrahim, Sattar and Kaleem are in jail in connection with the STF suicide bomb attack. Hamza’s name also cropped up more recently in the Mecca Masjid probe — Sheikh Sameer alias Nayeem, who allegedly helped people get into India from Bangladesh, mentioned Hamza’s name in the course of a narco-analysis test.

The Bangladeshi national also found a mention in a fourth FIR filed by the Hyderabad police in connection with the August 25 twin blasts in the city that killed 44 people.

Meanwhile, the Hyderabad police have brought two of the persons named in the fourth FIR to Bangalore to conduct narco-analysis tests: Abdul Kaleem who is already facing trial for the STF blast and Imran Khan, a bank employee, accused of providing shelter to Shoaib Jagirdar, a meat seller from Jalna in Maharashtra, who was first detained for the Mecca Masjid blast case but was later charged under the Passport Act for attempting to help Nayeem obtain a passport with fake documents.