The series of eight bomb explosions which rocked Sri Lanka's capital city Colombo and its neighbourhood on Easter day leaving nearly 300 people dead has flung the intelligence agency authorities into action over which group could be behind the planning and execution of the dastardly terror attack.

As the authorities investigate the bombings in Sri Lanka on Easter Sunday, their suspicion has zoomed on National Thowheeth Jama’ath, a relatively lesser known group that experts said promotes Islamic terrorist ideology.

After no terrorist group or militia outfit claimed responsibility for the suicide attacks, which killed accounted for the lives of least 290 people, and the Sri Lankan authorities have so far not identified any group as being behind them, even as they have arrested two dozen suspects.

National Thowheeth Jama’ath came into prominence mainly in Sri Lanka for vandalizing Buddhist statues. In 2016, its secretary, Abdul Razik, was arrested on charges of inciting racism.

The goal of National Thowheeth Jama’ath is not insurrection, said Anne Speckhard, the director of the International Center for the Study of Violent Extremism. Instead, it aims to spread the global jihadist movement to Sri Lanka and to create hatred, fear and divisions in society.

“It is not about a separatist movement,” she said. “It is about religion and punishing.”

“These attacks appear to be quite different and look as if they came right out of the ISIS, Al Qaeda, global militant jihadist playbook, as these are attacks fomenting religious hatred by attacking multiple churches on a high religious holiday,” she said.

The coordinated suicide bombings on Sunday, targeting members of Sri Lanka’s Roman Catholic minority and guests at hotels favored by foreign tourists, were similar to those carried out elsewhere by major Islamist militant groups, Ms. Speckhard said.

The island nation in the Indian Ocean, which was under the garb of decades of civil war that ended in 2009, has little history of militant Islamist violence.

In that internecine conflict, the Sri Lankan government, largely led by a Buddhist elite, put down a rebellion by ethnic Tamils, who are primarily Hindu but also include Muslims and Christians.