Roger Nsengiyumva was born as death squads roamed outside and relatives and neighbours were hunted down and slaughtered. By Rowan Mantell

Illuminee and Roger looking forward to a bright future in Norwich in 2007. Photo: Simon Finlay

The mother of Roger Nsengiyumva tells the family’s haunting story in a new book. Roger, Today he's a film and television star, up for an award at the BAFTAs, and about to celebrate his 25th birthday. But it is also the 25th anniversary of the genocide which left more than a million, including his father, dead.

For exactly 100 days Roger's mother, Illuminée Nganemariya, woke in her native Rwanda expecting to be killed. Hours after she gave birth to her only son, the killers came for her husband. Despite hiding in a pit for a week he was eventually caught and hacked to death by men who had just months before been guests at his wedding.

For the next three months Illuminée lived in unimaginable terror, hiding in bullet-pocked ditches, cowering in the blood-stained rooms of abandoned buildings as machete-wielding murderers rampaged through her country.

Miracle in Kigali by Illuminee Nganemariya with Paul Dickson

Once she escaped death when a gunman ran out of bullets; another day she left a hiding-place just as the building was raided and everyone sheltering inside was slaughtered. Every hour of every day, frantic with fear, assaulted, starving, she expected to be killed and still cannot fathom how she and Roger survived.

One of the countless tragedies of Illuminée's story is that of her husband's toddler son by his first wife who had died in childbirth. She kept David safe through weeks of genocide, only to lose him in the mayhem of a forced march through mountains. Fellow refugees helped carry him across the border to safety, but died of cholera in a refugee camp.

The roots of the genocide go back to the colonial era when Rwandans were divided into two groups – Hutu and Tutsi. Tutsis were given better education and jobs. Resentment grew among Hutus, who won control of the country at its independence in 1962. Twenty two years later an aeroplane was shot down, killing the Hutu president. Hutus were told to wipe out Tutsis.

After the outside world finally intervened to stop the killing, Illuminée and a group of other widows returned to her home city. The streets were strewn with dead bodies. Slowly she discovered what had happened to friends and family – terrible stories of the torture and massacre of men, women, children and babies.

For Roger, not a single relative on his father's side survived. Illuminée lost almost all her family. But a cousin who worked for Oxfam had survived and was given the chance to study at the University of East Anglia. Esther's husband had also been murdered and she asked Illuminée to accompany her to help look after her children.

When Esther returned to Rwanda, Illuminée knew she wanted Roger to grow up in safety rather than alongside the people who had killed his family. She and Roger were given asylum in Norwich, and eventually became British citizens. Illuminée is hugely grateful to the people of Norwich, who helped her, and continue to help her, cope with the effects of the trauma she lived through. And she is hugely proud of Roger.

Roger talk about the film:

His acting career began after the publication of Miracle in Kigale, Illuminée's account of the frenzy of violence which convulsed Rwanda in 1994, and of her escape, first on foot over mountains and eventually to Norfolk.

A film producer, staying in Norfolk, read about the book. He was putting together the film Africa United about a group of children travelling through Africa to the World Cup in South Africa – and still had to find the right person to play a football-obsessed Rwandan teenager. Roger, a keen footballer who once had trials for Norwich City, was auditioned and won the part.

Next came a documentary, Genocide Baby, following Roger's emotional return to Rwanda as a teenager. Roger, a pupil at City of Norwich School on Eaton Road, decided on a career in acting and went on to win several more film and television roles – including a part in Tomb Raider and the dangerously ebullient Londoner Dadir Hassan in the BBC thriller Informer, which is now shortlisted for Best Drama in the BAFTAs.

“He was born I the most stressful conditions imaginable…I am so proud of what he has achieved,” said Illuminée.

Miracle in Kigali, The Rwandan Genocide – a survivor's journey, by Illuminée Nganemariya with Paul Dickson, is published on the 25th anniversary of the murder of almost a million people. Dedicated to her husband and sister, two of the more than a million victims, it updates the original edition of the book. Price £12, with £2 from each sale donated to Glaven Valley Churches in north Norfolk for their work with Life in Abundance charity in Rwanda.