Thames Valley Police confirmed in a statement that three people died after an incident in Reading park, adding that a murder investigation has been launched on the matter, as a 25-year-old suspect has been taken into custody.
The statement also clarified that the case is currently not viewed as terror-related, however, "officers are keeping an open mind as to the motivation for the incident".
“This is not currently being treated as a terrorism incident, however officers are keeping an open mind as to the motivation for the incident and are being supported by colleagues from Counter Terrorism Policing South East", Detective Chief Superintendent Ian Hunter, Head of Crime, said in a statement.
Earlier, Sky News, citing unnamed sources, reported that the incident is believed to be "terror-related".
Earlier, the police confirmed that "a number of people" had been injured and taken to hospital after an incident in Reading park, announcing that one man had been arrested at the scene. A police cordon has been placed around Forbury Gardens, and people are asked to stay away from the area.
According to initial local media reports, two air ambulances were called to the park as reports emerged that at least 12 people had been stabbed, and at least 3 people had died during the attack.
The Telegraph earlier reported, citing sources, that "three individuals declared dead at the scene and two transferred to the emergency department of Royal Berkshire Hospital".
The number of those dead or injured has not been confirmed.
Earlier, police said that they were aware of reports of an incident in the Reading park, saying that "officers are on the scene and investigating the incident".
UK Prime Minister Boris Johnson. reacting to the incident, said that his "thoughts are with all of those affected" and thanked the emergency services on the scene.
UK Interior Minister Priti Patel expressed concern about the reports, noting that, "My thoughts are with everyone involved, including police and emergency responders at the scene".
Kit Malthouse, NW Hampshire's Minister for Crime & Policing, expressed sympathies to "all affected", urging not to speculate on the incident.
Twitter users shared alleged photos and graphic video from the scene.
One shared video showed an X2 Air Ambulance helicopter landing in the area.
The National Police Chiefs' Council has called against "speculation or sharing of video or images of the serious incident in Reading", advising that the curious follow Thames Valley Police updates on the situation.
Reacting to the incident, the leader of the Reading Council, Jason Brock expressed his gratitude to the police and emergency services, assuring they will have his support.
Earlier, he warned people against visiting the area, describing the scene as "a serious incident".
Earlier today, a peaceful Black Lives Matter demonstration took place in the park, and it is not known whether there is any connection to the incident.