Three people – Barnaby Webber, Grace Kumar and Ian Coates – were killed in the Nottingham attacks.
A 31-year-old man remains in police custody after being arrested on suspicion of murder.
Here is how the incident unfolded:
– 4.04am
Police were called to Ilkeston Road after two people were attacked by a man with a knife.
The two students, Barnaby Webber and Grace Kumar, both 19, were unresponsive when police arrived.
A witness told the BBC he saw a young man and young woman being stabbed.
The man, who did not give his name, said he heard “awful, blood-curdling screams” and looked out of his window to see a “black guy dressed all in black with a hood and rucksack grappling with some people”.
He told the broadcaster: “She was screaming, ‘Help!’ I just wish I’d shouted something out of the window to unnerve the assailant.
“I saw him stab the lad first and then the woman. It was repeated stabbing – four or five times. The lad collapsed in the middle of the road.
“The girl stumbled towards a house and didn’t move. The next minute she had disappeared down the side of a house and that’s where they found her.
“I’d say it all happened within five or six minutes. The attacker then just walked off up Ilkeston Road towards town, as calm as anything.”
– 5am
Police officers knock on doors in Ilkeston Road asking for CCTV footage, according to residents.
– Man tries to gain access to supported living complex
Police investigations have found that a man matching the description of the suspect tried to gain entry to a supported living complex in Mapperley Road but was denied entry.
– Man found dead
Police believe the suspect then attacked Ian Coates and stole his van.
A call was then received by a member of the public before police arrived to find the academy site manager dead on Magdela Road with knife injuries.
– 5.30am
The stolen van was then used to drive at three people in the Milton Street area.
Lynn Haggitt said: “He looked in his mirror, saw a police car behind him. He then quickened up. There were two people, two in the corner, he went straight into these two people.
“The woman went on the kerb, the man went up in the air. There was such a bang. I wish I never saw it. It’s really shaken me up.
“I went over. Perhaps I shouldn’t have gone over but I wanted to see if I could help.
“He (the van driver) backed up after he hit… and drove up Parliament Street.
“The woman was sitting up on the kerb. She looked OK. The man was laying down but then he got up, sat on the side waiting for an ambulance,” Ms Haggitt said.
She added: “I can’t believe he was able to get up after the head wound.”
One man was taken to hospital in a critical condition while two others are believed to have suffered minor injuries.
– Just after 5.30am
Police detained a man on Bentinck Road after he abandoned the van and approached officers with a knife.
The man was tasered and arrested on suspicion of murder.
– 7am
Nottinghamshire Police spoke of a “serious incident” and said multiple road closures were in place.
– 9.37am
The force confirmed three people died in the attack, with a 31-year-old man held on suspicion of murder.
Chief Constable Kate Meynell said: “This is an horrific and tragic incident which has claimed the lives of three people.
“We believe these three incidents are all linked and we have a man in custody.
“This investigation is at its early stages and a team of detectives is working to establish exactly what has happened.”
– 1pm
Armed police could be seen standing outside a property in Ilkeston Road.
– 2.30pm
Nottinghamshire Police said they were keeping an “open mind” over the attack’s motive while working alongside their counter-terror colleagues to “establish the facts”.
– 5pm
A vigil at Nottingham’s St Peter’s Church, in the city centre, was held.
It was attended by hundreds of people, mainly of university age.
The Bishop of Southwell and Nottingham, the Rt Revd Paul Williams, said the impromptu service was an opportunity to “pray for those whose lives have so cruelly been taken away”.
– Just before 6pm
Police confirmed two 19-year-olds and man in his 50s were killed in the attacks.
The force also said the families of the victims had been informed.