Three people are feared to have died after a multiple stabbing incident at a park in Reading.
A number of people have been rushed to hospital with stab wounds after being attacked in Forbury Gardens in the town centre.
A source has told Sky News and PA that they believe the incident is terror-related - though neither this nor any fatalities have yet been confirmed. A man arrested at the scene is believed to be Libyan, the BBC is reporting.
The casualties were taken to the emergency unit of the Royal Berkshire Hospital for treatment after an incident in Forbury Gardens, a spokeswoman told the PA news agency.
Two air ambulances and several police vehicles responded to the incident, with images on social media showing a significant police presence.
The leader of Reading Council Jason Brock tweeted: "Concerning reports from Reading town centre - please stay clear of the area as Police are dealing with a serious incident."
Freelance journalist Claire Gould, 33, who lives near the scene, told PA she saw the emergency air ambulance vehicles land on the nearby Kings Meadow on Saturday evening as a police helicopter circled overhead.
She described hearing lots of sirens and said surrounding roads and a retail park had been cordoned off by officers.
Thames Valley Police said on Twitter: "We are aware of reports of an incident in Forbury Gardens, Reading.
"Officers are on the scene and investigating the incident."
Home Secretary Priti Patel tweeted: "Deeply concerned to hear reports of an incident in Reading.
"My thoughts are with everyone involved, including police and emergency responders at the scene."
