These are the first photographs of a teenage mother who died in a fireball after running from her home in flames.

Rachel Osei, 18, was heard screaming in agony before collapsing on the pavement where she died from terrible burns.

Police believe Miss Osei, who was studying to be a PE teacher at Queen Mary's University, may have caught fire inside her house.

Three members of the public tried to extinguish the flames, but they were unable to save her.

Neighbours said Miss Osei’s four-year-old-son Kai was staying with relatives at the time of the tragedy, which happened early Sunday.

Investigators are treating her death as ‘unexplained’, but it is understood their main line of inquiry is that her injuries may have been self-inflicted.

Last night, her heartbroken father Jonathan Osei, 48, said he could not understand what had happened.

‘Rachel was at university training to be a sports teacher,’ he said. ‘She wanted to do well and provide for her son. When I heard about the fire I tried to call her on her mobile phone but there was no answer. I tried to protect her but I could not.

‘I loved Rachel, she was a lovely, lovely daughter. I named her after my mother. I had four children but now I have only three.’

The teenager's mother was said to be too upset to talk about the horrific incident Monday afternoon.

On Monday, a grieving male relative, believed to be her brother Justin, said Rachel's mother, Rosalind, did not want to talk about her death.

Speaking at the family home he said: 'No, we're not talking. My mother doesn't want to talk about it.'

Two bouquets of flowers have been left outside her semi-detached home, which has been cordoned off by police following Sunday’s tragedy.

Hannah Sirott and Rhianna Price, who left flowers said: 'We had the pleasure of studying music with Rachel for four years. She enjoyed music and rapping.

'She was a good person and she is definitely going to be missed by a lot of people.

'We have a couple of friends who know her family so we found out about her death that way. We just didn't want to believe it, it's shocking.

'She was an amazing mum to Kai and was always happy. She was friendly and funny and touched a lot of people's lives.'

Queen Mary's University, where the young mother was training to be a PE teacher, paid tribute today.

The Twickenham university said in a statement: 'We received the tragic news regarding Rachel's death with great sadness.

'Rachel was a promising Physical Secondary Education (PSE) student who will be missed by staff and students across the St Mary's community and we extend our deepest sympathy to her family and friends at this very sad time.'

Leeanne Muller, 18, from Wimbledon Chase, said: 'Rachel was bubbly and liked to talk - she was happy.

'She was enthusiastic about her future and used to tell me about how was going to be rich by doing what she loved doing. She liked rapping and playing sports.

'She used to talk about her son and how much she loved him and how she wanted him to have a good life. She was a very good mum.

'I've been her friend for a long time and used to look after Kai sometimes. He'll be devastated.

'I only found out what happened this morning and it's horrible, really shocking.'

Tributes were also left on Twitter for 'amazing' Rachel.

@RAGGAHMUFFINN wrote: 'She was and AMAZING Friend, Daughter, Sister & Mother to her beautiful son. May her soul rest in peace, Love you always Rachel Osei xxx.'

@maccagibson said: 'Rest in perfect peace Rachel Osei I live you and miss you! sad to no one of the best females I had in my life is gone! gunna miss u ghee'.

@RebeckahJ wrote: 'Thinking about my friendship with Rachel makes me realise she taught me so many things without realising it.. R.I.P Rachel Osei'.

The tragedy took place outside Miss Osei’s semi-detached home in New Malden, South-West London.

She was living in a property owned by the Wandle Housing Association, which often houses single mothers.

Miss Osei was studying at St Mary’s University, which is a few miles away in Twickenham. Neighbours described how they heard the noise of ‘terrible screaming’ shortly after 1am on Sunday.

Miss Osei was found with severe burns close to a level crossing at the junction of West Barnes Lane and Burlington Road.

Firemen, paramedics and police raced to the scene but she was pronounced dead at 1.45am. Layla Hamid, 20, said: ‘I heard this terrible screaming at about 1am. It was coming from the house opposite. Then the sound of the noise appeared to move down the road.

‘After that I saw loads of police cars and ambulances. It has been really crazy. It’s really sad.’ Yesterday a police forensic tent covered the spot where Miss Osei died, close to the entrance to a Tesco Extra superstore.

Detectives were piecing together her movements in the hours before the tragedy and were trying to identify what flammable substance was used.

Family friends said her mother, Rosalind Roberts, 46, and siblings Justin, 20, Nicole, 15, and Naomi, 14, were ‘devastated’.

The London Fire Brigade and the Metropolitan Police are conducting a joint inquiry into the cause of the blaze.

A Met spokesman appealed for the three people who tried to save Miss Osei to get in touch and tell investigators exactly what they saw.

‘The death is being treated as unexplained,’ the spokesman said. ‘We would like to speak to three members of the public who assisted in trying to save the woman’s life by trying to extinguish the flames at the time of the incident.’

A London Fire Brigade spokesman said two fire engines and 14 firemen attended but were unable to save Miss Osei. ‘She had suffered severe burns and was pronounced dead at the scene,’ he added.