Media playback is unsupported on your device Media caption Jonah Fisher on Burma remaining political prisoners

The military hat still hangs proudly on the wall of Major Win Naing Kyaw's house, on a peg just beneath what is clearly a favourite picture. The major, in sunglasses, stands stiffly, staring out sternly; next to him is his wife, Khin Moe San, with an infectiously radiant smile.

Smiles are now in very short supply. Khin Moe San has just been to visit her husband in prison. "He's not well", she says, shaking her head, before telling me he's been "sad and depressed" since President Barack Obama visited Burma (also known as Myanmar) last year.

High-level foreign visits are often accompanied by prisoner releases and this trip was no different. Of the 10 political prisoners serving life in the major's block in prison, nine were allowed to go free. Only he was left behind.

"The government clearly hates him," Khin Moe San told me sadly.

Image caption Mar Win Naing Kyaw, left, is not doing well, his wife, Khin Moe San, right, says

The major certainly has powerful enemies. Four years ago, he was arrested at Rangoon (also known as Yangon) airport.

After spending weeks in jail, he confessed to leaking sensitive details of Burma's military ties with North Korea to journalists. Under a law more than 60 years old, he was sentenced to death for revealing state secrets. As is now common in Burma, the sentence was then commuted to life imprisonment.

Khin Moe San tells me her husband's confession was forced, made after he had been deprived of food, water and sleep, and his family had been threatened. Whatever the truth, the major is considered by many to be a political prisoner.

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Earlier this year Burma's president set up a special committee to identify political prisoners and submit recommendations to the government as to who should go free.

But those like the major, who are put on the list, are not necessarily freed.

Tortured to death

For all the talk of democracy, it's not hard to guess who's blocking his release - the Burmese army is still hugely powerful.

Not many of the 133 names still on the latest list of political prisoners are straightforward. Often, the issue is about what exactly makes a prisoner "political".

Some human rights groups are unhappy that those who have taken part in violence are included. What if someone has been party to the most brutal of atrocities - should they be ruled out?

In a dingy room on the outskirts of Rangoon, I met up with one of the daughters of a student leader called U Sein. She showed me the only picture the family have of their father - a fresh-faced man from another era.

Image caption U Sein was part of the resistance, but was killed by his own side

In the 1970s and 80s, U Sein worked as part of the resistance against the dictatorship and then joined a rebel group called the All Burma Students' Democratic Front.

On the frontline in the northern mountains, relations between the young fighters soured. U Sein was among a group accused of being government spies. Fifteen were executed outright. The rest were buried up to their waists in the ground - beaten and left exposed to the elements for more than a week.

Having dreamed of bringing democracy to Burma, U Sein and 19 others ended up being tortured to death by their own side.

One of the men leading the students' interrogation and torture in the mountains was called Than Gyoung. He is now in jail. But much to the horror of the tortured students' families, he may not be there much longer.

Activists consider Than Gyoung to be a political prisoner - his name has been put forward by the committee for release.

Bo Kyi, himself a former political prisoner, said he considers all of the students, including Than Gyoung, to be victims of the system at the time - the products of a brutal military dictatorship, and the suspicion and paranoia it created.

Bo Kyi wants Than Gyoung released and then a meeting held with the families of the students, so that the killer can explain his actions and they can, he hopes, be reconciled.

If it happened, it would be an isolated example of Burma delving into its traumatic recent past.

The tentative democratic changes that have taken placed here in the last three years have been made possible by looking to the future, to avoid upsetting the army and its vested interests.

All are acutely aware that scratching too deep or looking too closely at recent history could threaten Burma's still-fragile reforms.

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