In the last of these attacks, unidentified men last night hurled three bombs one after another at the Grameen Bank branch at Nabagram village in Ullapara upazila of Sirajganj district, leaving bank employees Kona Khatun and Nurul Islam critically hurt.

A similar attack was made on the Brac office in Porsha upazila in Naogaon district on Tuesday night that severely injured four of the office staff. They are Area Manager Abdur Rashid, 34, Programme Officer Wahiduzzaman, 38, and employees Enamul Haq, 32, and Rezaul Karim.

Earlier on Sunday, Krishnakumar and Saiful Islam fell victim to another bomb attack on the Brac (Bangladesh Rural Advancement Committee) office in Kalai upazila sadar in Joypurhat district.

On yesterday morning, three powerful hand grenades were recovered from the premises of a Brac office in Rangpur Town.

The attacks are guessed to be made by Jagrata Muslim Janata Bangladesh (JMJB), as an arrested JMJB operative in a statement to a Bogra magistrate last Monday said the ultra-militant Islamist outfit has been carrying out and is determined to continue bombing NGO offices.

ATTACK ON GRAMEEN BANK
Our Bogra correspondent reports: A group of about three men arrived in front of the bank branch at 7:30 last night riding motorbikes, hurled three bombs into the office one after another and fled, locals said.

The attack critically injured Kona Khatun and peon Nurul Islam, who were working inside the branch office at Nabagram village under Ullapara upazila. They were rushed to a local hospital.

No-one was arrested until filing of this report at 11:00pm. Police were still clueless about the attack.

ATTACKS ON BRAC
A group of unidentified bikers hurled three bombs one after another at the Brac office in Porsha at around 9:30 Tuesday night and sped away, said local police.

The critically injured four Brac employees were first rushed to a local medical centre and, as their condition aggravated, they were later transferred to Naogaon Sadar Hospital.

Police arrested two people -- Noor Mohammad of Chakdebpara in Naogaon Sadar upazila and Apple Mahmud of Shitpati village in Porsha upazila -- at Matinagar village in Patnitala upazila with a motorbike at around midnight, suspecting their involvement in the attack.

Police said, on primary quizzing, the arrestees claimed to have gone to the spot out of curiosity, learning that some Brac employees died in a bomb attack.

The earlier attack in Kalai upazila was also made in the same manner. Kalai police said three youths on motorbike threw three bombs successively on the Brac office and fled.

Police so far have not arrested any one in this connection.

A five-member probe committee headed by Superintendent of Police (SP) ABM Shawkat Ali of Joypurhat district has been formed into the incident and asked to come up with its report within a week.

GRENADE RECOVERY
Our Rangpur Correspondent reports: Three powerful hand grenades were recovered from the premises of Brac office at Darshana in Rangpur Town yesterday morning.

A team of explosives experts from Rangpur Cantonment disposed off the grenades in an open field, about 150 yards off the office six hours after the detection.

Brac Regional Manager Nishanur Rahman lodged a general diary with Rangpur Kotwali Police Station in this connection.

Police officials seeking anonymity said the grenades were very powerful and the office and its staff had narrowly escaped a great danger.

But the officer in-charge of the police station termed the incident an isolated one. He said, "This incident has no connection with the bomb attacks carried out in other different places of the country."

Rangpur SP Mahbub Morshed told The Daily Star they are yet to detect who planted the grenades on the office premises.

Brac Rangpur Area Manager Abul Hossain said he saw a bottle shaped object wrapped with black tape at 6:45am in the backyard of the office. He took it up and found it to be unusually heavy.

Fearing it to be an explosive device, Hossain carefully put it back on the ground and informed the regional manager and other colleagues. The staff then started searching the whole office premises and found two more similar objects -- one in front of a training room and the other near a toilet.

Nishanur Rahman said, after detecting those objects, he promptly informed police, who reached the spot at 9:30am.

He said all Brac employees in the region are panic stricken.

At about 11:00am a team of explosives expert from Rangpur Cantonment came to the Brac office and took away the grenades. They detonated the grenades in an open field nearby at around midday in presence of police.

Police sources said the grenades were connected to Taiwan-made 12-volt batteries.

According to a police official the grenades were locally made but the technology is definitely foreign.

JMJB INVOLVEMENT
An arrested JMJB operative, Shafiqullah, in his statement given to First Class Magistrate Mostafizur Rahman Mridha in Bogra last Monday admitted that JMJB has been responsible for a number of bomb attacks on NGOs.

He said the JMJB bomb squad would continue attacks on NGOs like Brac and Karitas and on cultural activities that they consider as anti-Islamic until an Islamic revolution takes place in the country.

Shafiqullah, arrested with explosives in a fellow operative's house on January 16, one day after JMJB had carried out a bomb attack on a jatra (folk theatre) show at a village in Bogra, also said they use motorbikes for making these attacks.

Twelve operatives of Jama'atul Muzahidin, the former name of JMJB, arrested in Natore, also gave similar statements confessing to have carrying out bomb attacks on 'anti-Islamic' cultural shows and NGOs.