Image caption Zahran Hashim was not widely known in Sri Lanka until this week

A young mother of two in the coastal Sri Lankan town of Kattankudy sits in disbelief.

Mohammad Hashim Madaniya has found out that her brother, Zahran Hashim, is the alleged ringleader of a group of suicide bombers who attacked churches and hotels in Sri Lanka on Easter Sunday, killing at least 250 people.

She says she is horrified by what he has done and fears what could happen next. She has been interviewed by police but is not being treated as a suspect.

It's still not clear if Mr Hashim, who is accused of leading a group of bombers (alleged to include two sons of a wealthy tycoon), is alive or dead.

Wearing a white scarf, Ms Madaniya sits uncomfortably in the humidity of Kattankudy, a predominantly Muslim town overlooking the Indian Ocean.

She is clearly unhappy with the attention that she is getting.

She is the youngest of five siblings and Mr Hashim, believed to be around 40, is the eldest. She insists she has had no contact with her brother since 2017, when he went underground after police tried to arrest him over violence between ideologically opposed Muslim groups.

Since Sunday's attacks, a video has emerged in which a man believed to be Zahran Hashim appears pledging allegiance to the leader of the Islamic State (IS) group, Abu Bakr al-Baghdadi.

His is the only face visible among eight men who are said by IS to have carried out the attacks.

Sri Lankan police say there were nine attackers in total, including a woman, and that they were all homegrown. They were described as "educated" and "middle class" - with one having studied in the UK and Australia. Two were sons of a prominent spice trader who is now in custody, and one of the men's wives blew herself up during a raid on Sunday, killing her two children and several police officers, police sources say.

"I came to know about his activities only through the media. I never thought, even for a moment, that he would do such a thing," says Ms Madaniya of her brother.

"I strongly deplore what he has done. Even if he is my brother, I cannot accept this. I don't care about him any more."

Image caption Kattankudy's Muslims fear reprisals because the preacher came from their town

Her brother, a radical Islamist preacher, came to local prominence a few years ago after he posted several videos on YouTube and other social media platforms denouncing non-believers.

The videos triggered concern among other Muslims, who are a minority in Buddhist-majority Sri Lanka. Community leaders have said they raised concerns repeatedly with authorities but were ignored. Officials say they were unable to track him after he went into hiding.

But few would have expected a part-time preacher from a small town in eastern Sri Lanka to be able to organise the deadliest suicide bombings in this war-scarred country's history, attracting global attention and fresh scrutiny of links between local extremists and international groups like Islamic State (IS).

Image caption White flags are hung in Kattankudy to pay tribute to the dead

"We had a very good relationship during our childhood. He was very friendly with everyone in the neighbourhood. But for the last two years, he has not been in contact with us," said Ms Madaniya.

It is still not clear whether Mr Hashim had direct contact with IS or if he was a local jihadist who pledged allegiance to the group, which has claimed the attack.

Kattankudy is near the city of Batticaloa, where the Zion Church was bombed on Easter Sunday, killing at least 28 people.

The town, of less than 50,000 people, has now been thrust into the spotlight.

When I tried to find the ancestral house of Mr Hashim, many people were not willing to answer. People were scared to talk about him.

Since the bombings, the Muslim community has been on edge and apprehensive.

"That someone from our area has been linked to the attacks is really a worry for us. We are shocked and upset by it. Our community doesn't support hardliners. We believe in harmony and unity," said Mohammad Ibrahim Mohammad Zubair, the leader of the Federation of Kattankudy Mosques.

During my visit, Kattankudy was shut down in a day of protest against the carnage. Black and white ribbons fluttered along the main roads as a mark of respect for those killed.

Image caption The mosque Zahran Hashim founded had hundreds of followers - but is now empty

Mr Zubair said he met the radical preacher several years ago and spoke to him about his Islamic traditions, which differed from mainstream local practices. He said the community abhorred violence and that it was taking all steps to stop young people being radicalised.

Mr Hashim started as a small-time preacher but, his sister said, soon attracted attention and admiration in some quarters because of his teachings.

As his popularity grew. he went around the region preaching Islam.

After the mainstream Islamic groups refused to allow him to speak to their congregations due to his hardline views, he started his own outfit, the National Thowheed Jamaath (NTJ) in Kattankudy.

He also built a mosque close to the beach and held prayers and classes inside the building. After his controversial hate speeches surfaced on social media, locals say he was expelled from the NTJ. He simply vanished but continued to post incendiary videos from hiding. There is some scepticism locally as to whether he really cut links with the group he founded.

Sri Lanka's deputy defence minister Ruwan Wijewardene has said that a splinter group emerged from the original NTJ.

Image caption Mohammad Ibrahim Mohammad Zubair says the community does not support extremists

It is still not clear whether Zahran Hashim was one of the suicide bombers.

But one thing seems clear: as the government pointed out, those who carried out the bombings must have had some help from abroad.

During our conversation, Mr Hashim's sister also revealed that her elderly parents had left their home in the same area a few days before the Easter Sunday bombings and that she had not heard from them since.

"It makes me think that my brother could have kept in touch with them," she said. The authorities are also trying to trace Mr Hashim's younger brother.

Muslim leaders here maintain that Mr Hashim was an aberration and that their community, like all Sri Lankans, is mourning what they see as senseless attacks.

But the fear of reprisals in this small town is very real.