The Auckland-based mother and sister of one of the Sri Lankan Easter Sunday suicide bombers have been "co-operating fully" with NZ Police following the attacks that killed 257 people.
Abdul Lathief Jameel Mohamed was one of the terrorist bombers involved in the Easter Sunday attacks who attempted to blow up the luxury Taj Samudra hotel in the Sri Lankan capital Colombo.
Mohamed is believed to have botched his attempt to detonate his bomb at the five-star hotel and instead blew himself up at a nearby budget motel, killing two guests who had just arrived.
Mohamed's mother, Samsun Nissa, immigrated to Auckland, New Zealand, with her daughter who married a Sri Lankan New Zealander.
The family now live in a modest house in South Auckland, and refused to comment on the extent of their involvement in the police investigation into the bombings, spanning NZ Police and Sri Lankan authorities.
"We are just cooperating with police, whatever they want to know, that's about it," the believed brother-in-law of Mohamed told the Herald.
NZ Police confirmed they have been in touch with relatives of a suspect involved in the Sri Lankan bombings living in New Zealand.
"Police are aware that relatives of a person allegedly involved in the Sri Lanka bombings reside in New Zealand. We have engaged with the family and they are cooperating fully," a NZ Police spokesperson said.
Mohamed, 37, was one of nine people Sri Lanka's police have said staged the deadly Easter Sunday attacks.
Parked in the driveway of the South Auckland home for several days was a vehicle with a bumper sticker stating "Stop the occupation, free Palestine", with maps illustrating the encroaching Israeli occupation of the West Bank from 1947 to 2016.
Mohamed's descent into extremism
Ten years ago, after Mohamed's father, Abdul Latif, died, his mother, Samsun Nissa, moved the family to Colombo, renting the upper floor of a mansion in a majority Muslim eastern suburb.
After returning from studying in Britain, Mohamed moved into the property and fell in love with their landlord's daughter, Shifana, who came from an affluent meat-trading family.
They married before moving to Australia so he could pursue his postgraduate studies.
In an interview with the Daily Mail, Samsul Hidaya, another sister of Mohamed based in the UK, said her brother had been educated to the highest level but became increasingly withdrawn and intense as he descended into extremism.
"My brother became deeply, deeply religious while he was in Australia," she said.
"He was normal when he went to study in Britain, and normal when he came back.
"But after he did his postgraduate in Australia, he came back to Sri Lanka a different man.
"He had a long beard and had lost his sense of humour. He became serious and withdrawn and would not even smile at anyone he didn't know, let alone laugh."
"I just didn't think he would take it this far. I am still in disbelief. Something happened to him in Australia that changed his personality. He became silent and aloof."
Mohamed's identity came to light after Sri Lanka's defence minister, Ruwan Wijewardene, told a media briefing on Wednesday that one of the bombers had studied in the UK and done postgraduate studies in Australia before returning to settle in Sri Lanka.
Hidaya said her brother, born in 1982 to a family with six siblings, was from a wealthy tea trading family based near the central city of Kandy.
He was educated at the nearby Gampola International School before studying for his A Levels at the Royal Institute, a well-known international school in Colombo.
Mohamed, who had his first child in Australia, had moved back to Sri Lanka to live in the mansion his family previously rented.
His grandfather left him an extensive property portfolio when he died, including the family home in Kandy. As a result, the trained aeronautical engineer did not need to work.
"Before he died he was selling the family home," Hidaya said.
"He obviously needed a sum of money.
"But he never wanted for anything in his life. From time to time he sold or bought a property. He never had to worry about money like ordinary people do."