Full statement from Chief Constable Kate Meynell: As you all know, today there has been a shocking and tragic series of events which has led to the lives of three innocent people being taken and left another member of the public in a critical condition in hospital.
My thoughts are with all the families affected by this horrific incident, and we are working extremely hard to understand exactly what has happened.
I can tell you that a 31-year-old man has been arrested on suspicion of murder and remains in police custody.
We are not looking for anyone else in connection with the attacks and I can reassure the public that it is safe to visit the city centre – though there may be some road restrictions as we continue to establish what has happened.
Police were first called to Ilkeston Road just after 4am after a member of the public reported that two people, aged 19, had been stabbed in the street and were unresponsive.
We had a further call to another incident in Milton Street where the driver of a stolen van had attempted to run over three people. As a result, one man is in hospital in a critical condition while two others are believed to have suffered minor injuries.
The van was then stopped on Maple Street where a man was tasered and detained by officers on suspicion of murder.
A man in his 50s was also found dead from knife injuries in Magdala Road by a member of the public. At the moment, we believe that the suspect had stolen this man’s vehicle and driven it to Milton Street where he drove at members of the public.
We are still in the early stages of the investigation and need to determine the motives behind these attacks.
We are keeping an ‘open mind’ and are working alongside Counter Terrorism Policing to establish the facts – as we would normally do in these types of circumstances.
The families of all of the victims have been informed and are being supported by specially trained officers.
Officers have also carried out a number of searches at addresses across the city to gather evidence, but no further arrests have been made.
A dedicated team of detectives is investigating the circumstances surrounding these incidents and will continue to gather evidence over the coming days.
I want to thank those who live and work in our city for their patience and understanding in incredibly difficult circumstances. We will, of course, keep the public updated as soon as we are able to say more.
This is a very sad day for our city and we will do everything possible for the victims and their families.
• Nottingham incident update: Police not looking for other suspects but keeping an ‘open mind’