Sri Lanka's Deputy Defence Minister doubles down on claims bombings are related to Christchurch attacks

Blood stains are seen on the wall and on a Jesus Christ statue at the St Sebastian's Church. Photo / AP

Sri Lanka's government has reiterated its belief the Easter Sunday attacks were inspired by the mosque atrocities in Christchurch.

Sri Lanka's deputy defence minister Ruwan Wijewardene said their intelligence authorities believe there's a clear link to Christchurch.

"We believe that this is a reprisal ... the Christchurch incident motivated these guys to carry out these blast's on Easter Sunday [sic]," he said in a press conference today.

Wijewardene's claims come after it was revealed Sri Lankan security services were warned about a potential terror attack.

Ten days before the Easter Sunday bombings, a top police official warned about an "alleged plan attack" from a radical Islamic extremist.

A member of the National Thowheet Jama'ath group was found using social media to spread "hate speech against non-Muslims" following the Christchurch mosque shootings.

A Sri Lankan soldier stand guard in front of St Anthony's Church. Photo / AP

The New York Times translated a memo in which the high-ranking police officer said it had been observed the man was posting regularly online.

The document was titled "Information of an alleged plan attack" and was signed by Deputy Inspector General of Police, Priyalal Dassanayake.

"A person known as Milhan, maintains a social media account under the name Mohammed Milhan and interacts with the social media accounts of Zaharan," the memo said.

"It has been observed that he has been regularly updating accounts with hate speech against non-Muslims since the March 15, 2019, attacks on a Muslim mosque."

No direct link is mentioned between the Christchurch attacks and the Sri Lankan bombings.

Meanwhile, security experts in New Zealand have told the Herald and Newstalk ZB it is unlikely there is a link between both terrorist attacks.

Dr Paul Buchanan, director of 36th Parallel Assessments, said given the co-ordinated nature of the attacks it was unlikely they were planned so quickly.

"Christchurch seems to be a convenient justification for something that was being planned before March 15 and has more to do with ethnic-religious conflict in Sri Lanka," he said.