Monks pray on Tuesday beneath the Bodhi tree, the site of the first explosion on Sunday. Picture by Deepak Kumar

Patna, July 9: Investigators probing Sunday’s serial blasts in and around the Mahabodhi temple today detained four more persons, including a woman, for suspicious movement prior to the explosions at Buddhism’s holiest shrine.

The four suspects, aged between 20 and 30 years, were picked up from Boring Road locality in Patna on the basis of CCTV footage, which was scanned by a joint team of officials of the National Investigation Agency (NIA) and the Bodhgaya police. The quartet was seen near the temple about an hour before the first explosion under the sacred Bodhi tree — where the Buddha is said to have achieved enlightenment — around 5.40am on Sunday.

Patna city superintendent of police Jayant Kant confirmed that three youths and a young girl — all residents of Patna — have been detained for questioning. “We have already given information to the NIA about their detention. They will interrogate the four,” he told The Telegraph. Their identities are not being disclosed as yet.

But an arrest still eludes the police. Late on Sunday, the investigators had detained a 30-year-old youth on the basis of his voters’ identity card that was found in an abandoned bag on the Mahabodhi Mahavihara premises. According to police sources, the bag also contained a civara — the long-flowing saffron robes worn by Buddhist monks.

The youth is still under detention but police sources admitted that so far, nothing concrete has emerged on the basis of which he could be formally arrested.

City SP Kant refused to share more information about the four suspects detained today. “Since NIA is the prime investigating agency, the district police had nothing to do with the Bodhgaya blast incident. But we will cooperate with the investigating agency and provide information they need from us,” he told The Telegraph.

Initial interrogation has revealed that the four had gone on a tour to Bodhgaya.

A senior police official, who spoke under cover of anonymity, said the four detained today had checked in to a hotel in Bodhgaya only for two hours just after midnight on Sunday and returned to Patna. “However, their proof of identity submitted to the hotel management has been found to be genuine,” the officer said, adding that terrorists seldom use their real identities when booking hotels.

The investigators would like to know from the suspects why they visited the temple so early. They had reached the temple in a four-wheeler, which was parked in the vicinity of the Mahabodhi complex. They stayed for a while and suddenly left.

The video footage shows they reached the temple around 4.30am. “The credentials of the detained persons are being verified,” said an investigator.

The Union home ministry has meanwhile accepted the Bihar government’s request to take over the investigation of the serial blasts case. A government official said the proposal was sent to the NIA, which accepted it and informed the state home department late in the evening.

Three separate FIRs have been lodged with the Bodhgaya police station — relating to the blasts respectively at the Mahabodhi complex, Tergar monastery and the Giant Buddha statue complex.

Deputy inspector-general (Magadh range) Nayyar Hasnain Khan said a joint team of the NIA and the district police has been formed to crack the case. He, however, refused to divulge more information as “it would hamper investigations”.

The NIA is collecting telephone data from mobile phone towers in the vicinity of the temple complex. Investigators said the analysis of the call records as well as the CCTV footage might take some more time. “The CDR (call details record) of the mobile phones a few hours before and after the blasts may provide some clues about the attackers,” an investigating officer said.

Sources in the state police headquarters said personnel of the Anti-Terrorism Squad (ATS) from Mumbai (Maharashtra) and Hyderabad (Andhra Pradesh) visited the explosion sites on Tuesday and gathered information about the explosives used to trigger the 10 blasts.

The security of the temple has been handed over to the Central Reserve Police Force (CRPF) and the Bihar Military Police (BMP). The BMP will look after security inside the temple complex while the CRPF will be in charge outside. Security guards of the Bodhgaya Temple Management Committee will assist the BMP inside the temple.

The preliminary probe has found a timer device and traces of ammonium nitrate similar to that used by modules of banned terror outfit Indian Mujahideen (IM) in some previous attacks in the country. The cylinders used to pack the explosives are also used by Maoists to trigger explosions, police sources said.

A report from Darbhanga said an NIA team posted wall-posters of 12 absconding members of the Indian Mujahideen at different places of the town.