Mr Uzomah, who is married with two children, is now said to be in a 'stable' condition with non-life threatening injuries.
He is a supply teacher who had been working at Dixons Kings Academy in Bradford for only four weeks.
The incident happened at 8.50am, just moments after the Year 10 science lesson began.
A 13-year-old girl said she saw Mr Uzomah 'hunched' over in the corridor bleeding from the stomach.
'We were in the classroom next door and it was really hectic and then we heard that a teacher had been stabbed by a student,' she said.
'We came out of our classroom and saw him on the floor, hunched over, bleeding. It was horrific and a bit scary.'
The boy had been at the secondary school for around a year and it is understood that there had been problems with his behaviour.
Reports suggested the row over the phone had happened in class yesterday and that the teacher had been stabbed when he tried to take the mobile off the teenager.
A 15-year-old pupil said: 'I heard the boy stabbed the teacher because he took his phone off him. I was disgusted.'
Pupils were initially told to stay in their classrooms while a major police search was launched for the teenager, who cannot be named for legal reasons. Some anxious parents turned up at the school gates fearing for their children's safety but headteacher Neil Miley told them students would not be sent home.
Asked about his decision, Mr Miley said: 'Because I think it's important that we make sure there's consistency for our students, as students need to be safe and secure.'
Meanwhile parents of pupils who witnessed the attack were summoned to school to accompany their children to give police statements.
Before making the arrest, police described the pupil as an Asian boy who was wearing his school uniform. Detective Superintendent Simon Atkinson said a boy was arrested in the city centre.
He also confirmed the teacher suffered a 'single stab wound to his stomach' and his injuries are 'not life threatening'.
Mr Uzomah worked across Bradford and Leeds as a supply science teacher to help fund his own higher education. The accomplished civil engineer spent his spare time working towards a PhD at the University of Salford.
He lives in a £150,000 semi-detached home in the north of Leeds with his wife Uduak Imeh-Uzomah, 42, and their children Samuel, 12, and Glory, 11.
Last night friends said he had often complained about the 'naughty' behaviour of the children he taught.
His next-door neighbour described him as a 'lovely guy' who is an asset to the community. He added: 'We have spoken about how naughty the children were.'
Meanwhile former pupils posted tributes to Mr Uzomah, who is originally from Nigeria, on Twitter yesterday as news of the attack spread.
One wrote: 'I can't believe my old science teacher Mr Uzomah got stabbed today so upsetting considering his age and how much of a nice person he is.'
The attack comes just over a year after teacher Ann Maguire, 61, was stabbed to death in class at Corpus Christi College in Leeds by pupil Will Cornick, 15.
He admitted murdering the popular teacher and was given a minimum 20-year term last November.
- Daily Mail