Two of the three people killed in attacks in Nottingham this morning were students at the University of Nottingham.
Police declared a "major incident" after two people were found dead in the street in Ilkeston Road just after 4am.
A witness reported seeing a young man and young woman being stabbed there.
Officers were then called to Milton Street, about a mile away, where a van driver had attempted to run over three people.
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A third man was also found dead in nearby Magdala Road.
Police have arrested a 31-year-old man on suspicion of murder and he remains in custody.
Video appears to show a suspect on the ground next to a white van as three officers carry out the arrest on Bentinck Road.
Photos - apparently of the van used in the attack - show small circular cracks at the bottom of the windscreen. There also appears to be damage to the bumper.
A bag can be seen on the road next to the van, but it's unclear if it belonged to the attacker.
Police said they are keeping an "open mind" over the motive and are not looking for anyone else, but are working alongside terror police as is normal in such a case.
Read more:
A timeline of how 'major incident' unfolded
Sky News correspondent Becky Johnson reported a "flurry of activity" at around 12.30pm as armed police cut off Ilkeston Road.
She said two young women were eventually put in the back of a marked car after police appeared to enter a commercial property.
