Security personnel inspect the interior of St. Sebastian's Church in Negombo on April 22, 2019, a day after the church was hit in series of bomb blasts targeting churches and luxury hotels in Sri Lanka. (Photo by ISHARA S. KODIKARA/AFP/Getty Images)

The US may initiate legal action against the Sri Lankan Islamist group linked to the Easter Sunday bombers since American nationals, including an official from the Department of Commerce, were among those killed in the carnage, according to a media report.

The US may pursue legal action against the group linked to the Easter Sunday bombers once the investigations are completed, The Sunday Morning reported.

Quoting US government sources, the paper said that since there were US citizens among those killed in the 21 April attacks, the US may pursue indictments against those involved, in a US court.

At least 45 foreigners were killed in the attacks which hit three posh Colombo hotels and three Catholic churches as well as a small lodge in Dehiwala.

Among the US citizens killed was Chelsea Decaminada, an International Programme Specialist with the Department of Commerce. She was having breakfast at one of the three posh hotels in Colombo when the suicide attack took place.

Nine suicide bombers, including a woman, carried out a series of devastating blasts that tore through three Catholic churches and three high-end hotels frequented by tourists in the country’s deadliest violence since the devastating civil war with the Liberation Tigers of Tamil Eelam ended in 2009.

Though the Islamic State claimed the attacks, the Sri Lankan government has blamed the local Islamist extremist group National Thawheed Jamaath (NTJ) for the bombings.

Following the April 21 attacks, Sri Lanka sought the help of the US to assist with the investigations.

The report said that a few Federal Bureau of Investigation (FBI) investigators were still in Sri Lanka.

The report also noted that countries like the UK and India may also seek to pursue legal action against the Sri Lankan Islamist group as nationals of these nations were among those who were killed in the attacks.

“The UK, Australia, India, the US, and other nations which lost citizens in the attack could seek to exercise criminal jurisdiction over those who were involved in or supported the attacks, based on their own laws and multilateral treaties to which those nations, as well as Sri Lanka, are parties,” it said.

Apart from the US, India, the UK, and Australia were among a number of countries assisting Sri Lanka in the investigations in the immediate aftermath of the attacks by providing investigators.

It has become clear that a local group had been influenced by the teachings of the Islamic State to carry out the attacks, it said.

The Easter Sunday bombers, while not members of ISIS or Islamic State, had been influenced by IS to carry out the attacks, the report said.

While Sri Lankan authorities asserted that they had dismantled the local cell involved in the April 21 attacks, there are still fears that IS propaganda may reach others, and may lead to plans to carry out similar attacks in the future, the report said.