A Crystal Palace fan described as a 'friendly, genuine lad' was among those killed when a Croydon tram derailed.
Dane Chinnery, 19, has been named as one of those who died in the morning rush hour incident in Croydon, south London, on Wednesday.
The driver of the tram is being questioned by police amid suggestions it failed to brake before taking a corner at speed.
Investigators said the vehicle was travelling at a "significantly higher speed than is permitted" and are probing whether the driver had fallen asleep.
More than 50 people were injured when the tram left the track and flipped on its side.
Tom Dale, 20, was on the tram and recalled nodding over to his old school friend Mr Chinnery, who was already sitting on the tram when he boarded.
The pair, who went to Addington High School together and took part in performing arts, were on their way to work.
Mr Dale said that after the tram crashed he was looking for his friend, and asking, "Where's Dane? Where's Dane?", but all he could see was Mr Chinnery's boot where he had been sitting.
"It was like walking out of a war zone," the chef said.
Mr Dale, who was badly bruised, said of Mr Chinnery: "He was just a friendly, genuine lad, did no harm to nobody really. No one deserves for this to happen to them."
Friends of Mr Chinnery, believed to be a Crystal Palace fan, posted tributes on social media, with babyfaacecay tweeting: "Rip to a old school friend who lost his life today in the tram accident; Dane chinnery we will miss you such a lad&a full of smiles."
Tom Curtis wrote on Twitter that he spoke to Mr Chinnery last week, adding: "R.I.P Mate taken to soon."
Social media users were encouraged to share a post calling for a minute of applause at Crystal Palace's next home game on November 19.
The post said: "He was red and blue all the way through, and simply loved palace."
It concluded: "RIP Dane."
London mayor Sadiq Khan, who visited the scene on Wednesday, warned the death toll could increase.
British Transport Police (BTP) said forensics teams are expected to stay at the crash site until Thursday evening at the earliest, and identifying the dead may be a "complex and lengthy process".
The tram was travelling from New Addington to Wimbledon via Croydon when the accident happened at 6.10am.
Scenes after the crash were described as "total carnage" after the two-carriage tram tipped over in heavy rain next to an underpass.
Survivors rescued from the wreckage said the tram failed to brake in its usual place at a bend on the track after speeding up. One said the driver told them he thought he had "blacked out".
Martin Bamford, 30, from Croydon, said he recalled the tram "speeding up", adding: "Everyone just literally went flying."
Speaking outside Croydon University Hospital, where he was being treated for fractured or broken ribs, he said people were screaming and there was "blood everywhere", describing the scene as "like something out of a film".
He added: "There was a woman that was on top of me ... I don't think she made it at all. She wasn't responsive. There was blood everywhere."
Asked about the driver, he said: "I asked him if he was okay. He said 'yeah'. I said to him, 'what happened?' He said he thinks he blacked out."
The 42-year-old driver, from Beckenham, was arrested on suspicion of manslaughter and taken into custody for questioning.
The crash is being probed by BTP and the Rail Accident Investigation Branch (RAIB).
BTP Assistant Chief Constable Robin Smith said officers were also investigating "a number of factors".
Initial findings of the RAIB show the tram came off the tracks as it was negotiating a "sharp, left-hand curve" with a speed limit of 12mph.
A spokesman said: "Initial indications suggest that the tram was travelling at a significantly higher speed than is permitted."