The offices of two leading non-governmental organisations in northwest Bangladesh have been attacked with firebombs, injuring six people, police said Thursday, blaming Islamic militants. The assaults on the offices of the Bangladesh Rural Advancement Committee (BRAC) and Grameen Bank occurred Tuesday and Wednesday, police said. Three grenades were recovered from another BRAC office on Wednesday before they could explode, police said. "We suspect that a group with an Islamic ideological bent hurled the petrol bombs at the two offices," a senior police official in northwestern Rajshahi told AFP, speaking on condition of anonymity.BRAC, the country's largest NGO, has been at the forefront of the country's fight against poverty. Grameen Bank is known worldwide for its pioneering work giving small loans to the poor to help them set up businesses. The incidents, in three separate districts of Rajshahi, follow a series of unexplained explosions and attacks over the past year on targets including religious shrines, cinemas, academics and opposition rallies. The opposition has accused the government - a four-party Islamist-allied coalition led by Prime Minister Khaleda Zia's Bangladesh Nationalist Party - of supporting fundamentalist groups they claim are involved in the attacks. The government has dismissed the accusation saying it is working hard to track down the culprits.