Six months on, the BBC's Mark Dummett pieces together what happened during a border guard mutiny in Bangladesh and examines claims that suspects have been tortured and killed.
It was nine in the morning and, like teenagers everywhere, Nadeet was on his way to bed.
His sister was already at school, his father had said goodbye and gone to work, and his mother had just left for the gym.
Nadeet was tired after a night spent chatting to friends and tinkering with the old car he had recently bought with his father, the first the family had ever owned.
But he did not get much sleep that day.
Nadeet lived in Pilkhana, the British-era military camp in the heart of the Bangladeshi capital, Dhaka.
Its rose gardens, deer enclosure and sports fields are a world away from the mayhem of the overcrowded streets outside.
On that morning in February, soldiers of the Bangladesh Rifles (BDR) border security force were about to turn it into a killing zone.
By the time their revolt collapsed the following day, 74 people had lost their lives, and Bangladesh had been dragged to the brink of a nationwide armed conflict, as the mutiny spread to camps elsewhere.
The first Nadeet heard that something was wrong was when he was woken up by the family's housekeeper.
"Then all of a sudden there were more than 25 people firing at my house," Nadeet remembered.
"I could see the ceiling was falling off. I didn't know what to do, so I called up my friend, and I told him, listen bro' this could be the last time I'm talking to you, they're killing everyone in the BDR. So you must let the army know, and please be fast.
"Then I saw them break into my house. They were so ferocious. They were like, where are they, where are the kids, where are the wives?" Nadeet told the BBC World Service's Assignment programme.
He was one of the many eyewitnesses who helped us piece together what happened during the course of the mutiny.
He described his escape and how he hid under a bed until it was finally safe to come out.
Only then did Nadeet discover what had happened to his father, Colonel Mojibul Haque, a senior officer.
He was shot and then thrown out of a second-floor window by his men, after he tried to restore order.
Fifty-six other officers were also gunned down or stabbed to death, as were the wife and two civilian house guests of the BDR's commander, Major-General Shakil Ahmed, as hundreds of soldiers went on the rampage.
The mutilated bodies were then dumped in mass graves, sewers and the camp's incinerator.
"Every day I ask myself why did such a brutal thing take place," Nadeet's mother Nehreen, who survived by hiding in the gym, said.
"My husband and the officers used to work so hard for these soldiers' benefit. My husband was a true soldier. He was such a loving and joyful character."
The question of what led to such brutality is one that has perplexed Bangladeshis ever since.
When the mutineers themselves telephoned the BBC's Bengali Service, they blamed their revolt on bad pay and years of mistreatment by corrupt officers.
They eventually gave up after the government threatened to send tanks into Pilkhana, while also promising to look into their complaints.
But Bangladesh has a history of murky political conspiracies, so many people assumed that this too must have been part of a wider plot.
Faruq Khan, the minister in-charge of co-ordinating the investigation into the mutiny, told me he thought that a hard-core group of about 20 soldiers had exploited the grievances of the other men to destabilise the government, which had been elected only two months earlier.
It is a particularly understandable view given the family history of the new Prime Minister Sheikh Hasina.
Thirty five years ago the army murdered her father, the country's first prime minister, along with most of his family, and Hasina has survived three assassination attempts since.
"I think this was planned," Faruk Khan said. "If you look at how large the matter was, that is proof that there was a planning."
The government straight away promised to uncover what was behind the revolt and administer justice as speedily as possible.
Six months later, the police are still working on their largest ever criminal case. There are about 5,000 suspects, and the FBI and Scotland Yard have lent a hand.
But their investigation has been overshadowed by claims that the unit conducting interrogations is torturing suspects, and may even have killed some of them.
The BDR itself admits that 40 of its men have died since February, but says seven committed suicide while the rest had heart attacks or died of other illnesses.
Nur Khan Liton, of the Dhaka-based rights organisation Ain O Salish Kendra, said he had seen torture marks on the corpse of one BDR soldier, Mubarak, who according to official records, took his own life.
"I don't believe it, because I saw one dead body. I saw that a toenail of that BDR member had been pulled out," he said.
His claims echo those of the wife of another BDR soldier, who spoke to the BBC on condition of anonymity, because she had received phone calls threatening her with arrest if she spoke out publicly.
She described seeing her husband for the first time after his detention.
"I saw my husband seated on the floor. He could barely move because his whole body was bruised, and so were his eyes. At first I didn't recognise he was my husband.
"Then he shuffled nearer to me. He was crying. I was crying. I said 'where've you been'? He said, 'Don't ask me that. I'm alive. You've prayed for me. That's why I'm alive. But don't ask me where I've been'."
The police and the army deny the claims that prisoners are being abused, and the state prosecutor insisted that confessions had not been extracted by force.
"Torturing is not done in Bangladeshi prisons," Faruk Khan said. "The interrogators in this incident have been clearly instructed by the government that they must not go beyond the law."
Rights groups are also worried that the prisoners may not receive a fair trial.
Lawyers of some of the men say that they have been prevented from meeting their clients, in breach of the Bangladesh constitution.
The Supreme Court is currently debating whether or not the border guards should be tried under military law.
The fear is that the army's desire to punish the mutineers will outweigh all other considerations.
This may make it less, rather than more, likely that the full story of what happened ever emerges.