Image caption Islamist militants would have killed Shishir Sarker if they'd known he was a Hindu

When five armed Islamist militants stormed a restaurant in Dhaka, Bangladesh, on 1 July 2016, 29 people lost their lives. Emerging from the appalling, bloody debris are stories of immense courage. There are also unanswered questions about what happened to some of those who died.

It was about 20:45 on a Friday evening just before the Islamic festival of Eid. The restaurant - the Holey Artisan Bakery and O'Kitchen in Gulshan, Dhaka's leafiest, most exclusive area - was filling up, mostly with Japanese and Italian customers.

Suddenly, the five young militants burst in shooting and began hacking at the diners with sharp weapons.

Shishir Sarker, one of the Holey Artisan's chefs, was coming out of the refrigerated chiller room with a plate of pasta when he heard shouting.

"Then I saw one of the attackers - in one hand he had a sword or machete, and a gun was slung across his chest," Sarker recalls.

As a Hindu, he had good reason to be afraid - if the Islamist militants found out his religion, it would be a death sentence.

"At that moment, a Japanese man shouted to me: 'Help me!'," he says. "I turned and went back inside the chiller, and helped him in too."

Image copyright AP Image caption Police walk past the Holey Artisan Bakery

There was no latch to lock the chiller from the inside, so the two men pulled on the door to keep it shut.

"The Japanese guy asked me who those men were. I said I didn't know, but don't worry, the police are coming."

For nearly two hours the men stayed quietly inside.

"It was really cold. We did some exercise to try and keep warm - sit-ups holding the door pulled shut," Sarker says.

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Listen to Siege at the Holey Artisan Bakery on BBC Radio 4's Crossing Continents at 11:00 GMT on Thursday 12 July, or catch up again on iPlayer

The documentary can also be heard on the BBC World Service's Assignment - click here for transmission times and to listen again

Then came a terrifying moment - one of the attackers tried to open the chiller door.

"We held on to it very hard and he failed. He went away, but now they knew someone was inside."

And 10 or 15 minutes later the militant came back.

"We were so cold, we were losing our strength," Sarker says. The attacker hauled the door open.

Image copyright Getty Images Image caption A woman shows a mobile phone picture of her brother-in-law, a restaurant employee

"He told me to come out. I was so frightened I immediately fell on to the ground and lay there. I thought if I was standing, he might chop me with his machete. I was repeatedly saying: 'For Allah's sake, don't kill me.'"

Assuming he was Muslim, and therefore not a target, the gunman told him to go and join his colleagues on the other side of the restaurant.

"I crawled on my hands and knees over dead bodies and blood. Then suddenly I heard two shots. The Japanese man with me in the chiller was dead."

Sarker sat at a table with other members of staff, all of them with their heads down. After 02:00, one of the militants asked who the chef was. His colleagues pointed at Sarker. He was taken to the kitchen.

"They asked me what food we had - if we had sea bass and shrimps. I said, yes we had. They told me to fry it, and decorate it nicely on a plate."

While Sarker was cooking, one of the militants came into the kitchen.

Image copyright Getty Images

"He asked me what my name was. I just said my name was Shishir - I didn't tell him my second name because that would have revealed that I'm Hindu."

Perhaps the militant was suspicious. He asked Sarker to recite from the Koran.

Sarker calmly carried on frying sea bass. And he recited Koranic verses.

"All my life I've had Muslim friends, so I knew some Surah [chapters of the Koran]. But I was so frightened. I was thinking - would I satisfy him?"

In keeping with Islamic tradition during Ramadan, the food was served before dawn to the Muslim hostages and to the staff.

"I was so scared, when I ate I couldn't swallow the food. But I thought if I didn't eat, they would think I wasn't going to fast the following day, and then they would guess I wasn't Muslim," says Sarker.

Soon after sunrise, Operation Thunderbolt - a commando-led assault with armoured personnel carriers - ended the siege. The five militants lay dead. Sarker and his surviving colleagues were rescued.

Life will never be the same for this unassuming young chef. He is working again, but still traumatised by that hellish night.

"I don't see any future. I can't sleep properly. Whenever I'm alone and I think of that night, I just can't do anything - I feel terrified."

The student who refused to abandon his friends

Faraaz Ayaaz Hossain, a 20-year-old studying at a university in the US, was home in Dhaka for the holidays.

He had arranged to meet two old school friends at the Holey Artisan that night - Abinta Kabir, a US citizen from a Bangladeshi family studying at the same university, and Tarishi Jain, who was Indian, a Hindu and a student in California.

Hossain and the young women had just taken their seats in the restaurant when the attack began. A family driver called his mother and told her something was amiss.

"As soon as my mum heard, she barged into my room and said, 'I'm going'," says Faraaz's brother Zaraif. "She put on her shawl, took her phone, and ran - I ran behind her.

"When we got there people started telling us they'd heard the assailants shouting: 'Allahu Akbar!' That's when it hit us this must be more serious than an armed robbery or something."

After 21:30, some 45 minutes after the attack had begun, a number of the restaurant staff managed to escape via the roof. They appeared on the street, and Zaraif and his mother homed in on one of the waiters.

"We asked, 'Have you seen a boy with two girls?' We were showing a picture of Faraaz on our phones. And he said, 'I've seen them, they're hiding under a table.'"

But other details were chilling.

The waiter said everyone who was foreign was being kept in one section. And everyone who was considered Bangladeshi and Muslim was put into another section.

"At that moment my mother turned to me and said: 'Tarishi and Abinta won't be let go. I'm so scared, because I know my son - I know Faraaz, and he's not going to leave his friends.'"

Image caption Hossain (left) was a keen Manchester United supporter

When the siege ended, Faraaz and both his friends were dead - murdered by the militants. And an incredible account emerged of Faraaz's last moments, validating his mother's fears.

"So what we heard about what transpired was that, well… Faraaz was a Bangladeshi and a Muslim and therefore, logically, he would have been let go by the terrorists," says his brother.

"But when he was told to leave, Faraaz said: 'What about my friends?' And when they were denied freedom, he said: 'I'm not leaving them.'"

The story of Faraaz's selfless act has brought international recognition, including the Mother Theresa Memorial International Award for Social Justice, which was conferred posthumously on this bright young man.

In Bangladesh too, he has been celebrated.

"In remote places, people are having discussion meetings saying: 'Faraaz is Bangladesh, this is who we are - not the terrorists,'" says Faraaz's grandfather, the industrialist, Latifur Rahman.

"In Banshkhali, they named a square after him. The other day a professor at one of our universities gave birth to a boy and named him Faraaz - because, she said, she wanted him to have the same values as Faraaz."

This is heartening for the family. But it cannot replace the mad-keen Manchester United fan - a young man destined, says his grandfather, for leadership and success.

"I struggle with it every day. I understand what he did, I deeply admire what he did, but I struggle with understanding how one could do that. I struggle because I don't have the guts. I don't have the strength to do what this young boy did. I wish he was here with me."

The mystery of the lost cook

Zakir Hossain Shaon's family home on the southern outskirts of Dhaka feels like a million miles from the upmarket restaurant where he was employed. Down a track that skirts a pond covered in water hyacinth, his parents, brothers and sister live in a tiny one-room house with an adjoining kitchen.

Shaon, 18, had worked at the Holey Artisan for about a year.

"He adapted quickly to that job and his cooking duties," says his father, Abdus Sattar.

"All his colleagues loved him because he was the youngest," says Zakir's mother, Maksuda Begum.

On the evening of 1 July, Shaon was at work. He called his mother and told her he had been paid an Eid bonus, and would be coming home the next day, or the day after.

It was many hours before his parents found out about the attack - as it was the month of Ramadan, they were not watching television that evening.

In the morning, they were told about it by neighbours, and headed to Gulshan with Shaon's picture. They went from one police officer to another showing their son's photo. They talked to countless people on the streets. No-one knew anything.

At 22:00 that night, Sattar was in Gulshan police station. He says an officer there told him his son was alive, but that he could not say where he was.

Meanwhile, on local TV, pictures of Shaon were shown. They were taken sometime before 03:00 on 2 July, while the militants were still inside the Holey Artisan.

In them, Shaon is sitting in the back of a police vehicle, officers holding his arms. He is bleeding from the chest, but he is clearly conscious.

Somehow he had escaped the siege. So where was he now?

Image copyright Getty Images

On the morning of 3 July, Shaon's parents got a call from a surviving member of the Holey Artisan's staff. He told them their son was in Dhaka Medical College Hospital.

They rushed to see him. It was deeply distressing. He looked as though he had been beaten. There were marks on his legs, and he had a black eye which was not there on the TV pictures. He slipped in and out of consciousness.

"Every time he came to his senses he said one thing - 'Don't hit me please, don't beat me any more. Let me go,'" remembers his mother.

"The police grabbed him, and they tortured him. They hit him on the head. They kicked him. They indiscriminately beat him," she claims.

The chief of counter-terrorism for Dhaka Metropolitan Police, Monirul Islam, says Shaon was not in police custody.

"He was injured while he was trying to escape [from the restaurant]. He was taken to the hospital after Holey Bakery incident, at midnight I think. We are not sure who took whom to the hospital."

Dhaka Medical College Hospital can find no record of admitting Shaon, so the date and time he arrived cannot be confirmed.

His father tried to make a complaint to the police. "They didn't pay any heed to it," he says.

Shaon died on 8 July - a week after the siege. His family are still looking for answers.

On 11 January, the Holey Artisan Bakery reopened, albeit in a different location. The previous Friday, Dhaka police said one of the alleged masterminds of the siege had been shot dead. The shockwaves from the attack continue to reverberate across Bangladesh.

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