The stabbing attack at a park in southern England that left three people dead and three others injured on Saturday is being investigated as a "terrorist incident," police officials said Sunday.
It happened around 7 p.m. (local time) at Forbury Gardens in the town of Reading, the Thames Valley Police said. A Black Lives Matter protest had been held there earlier in the day, though the police said earlier that the stabbings were not connected to the demonstration, The New York Times reported.
A 25-year-old man was arrested at the scene on suspicion of murder on Saturday and remained in custody on Sunday.
"Incidents of this nature are very rare, though I know that will be of little comfort to those involved and understand the concern that this incident will have caused amongst our local community," Chief Constable John Campbell said in a statement on Sunday.
The suspect meanwhile was identified by a security source as a Libyan national. Speaking to CNN, the security source named the suspect as Khairi Saadallah. The source, on condition of anonymity, informed CNN that mental health was considered to be a factor in the assault, which contributed to the reasons as why the police took some time to declare it a terrorist incident.
Saadallah, who is currently in police custody, is under investigation by the UK's Counter Terrorism Policing unit after the knife attack in Reading's Forbury Gardens on Saturday afternoon.
The British media, citing unnamed government sources, reported that the security services looked into him last year, based on a suspicion of planning terrorism abroad, but found no evidence that he posed a threat.
UK Prime Minister Boris Johnson said on Sunday that he was "appalled and disgusted" by the incident, but that he saw "no reason" to raise the country's terror alert level.
"I am appalled and disgusted that people should lose their lives in this way and our thoughts are very much with the families and friends of the victims today," he said.
( With inputs from ANI )