Blasts in Sri Lanka killed more than 253 persons on Easter Sunday. (Photo:Getty Images)

Some of the suicide bombers who carried out a series of blasts in Sri Lanka on Easter Sunday had travelled to India to possibly train for terrorism, the Sri Lanka Army chief has said.

"They had gone to India, Kashmir, Bengaluru, Kerala state. Those are the information available with us," Lieutenant General Mahesh Senanayake said in an interview to BBC World.

On bombers' motive to travel to India, the Sri Lankan Army commander said the exact reason is not yet known.

"Possibly for some sort of training or to make some more links towards the other organisations outside the country," Sri Lanka Army chief Mahesh Senanayake added.

At least nine suicide bombers were responsible for the deadliest attack in Sri Lanka in a decade on April 21. President Maithripala Sirisena had blamed the security establishment for failing to communicate several warnings they had about potential attacks, including that from India hours before the first bomb.

When asked about these intel warnings from India and other quarters, the Sri Lankan Army Commander said they had received information and intelligence-sharing.

"Situations and military intelligence on a different direction and the others were different and there was a gap that everybody could see today," Mahesh Senanayake said.

The National Investigation Agency (NIA) has carried out several raids in Tamil Nadu and Kerala to unearth Indian links with the Sri Lanka blasts that killed more than 253 persons on Easter Sunday.

After the arrest of Riyas Aboobacker, the NIA established the presence of Islamic State sleeper cells operating in Tamil Nadu.

Riyaz Aboobacker of Kerala had earlier admitted to following Sri Lankan bomber Zahran Hashim and Zakir Naik.

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