A stabbing attack in a park in south-east England, in which three people were killed, was described on Sunday by the UK police as an act of terrorism.
The authorities initially said the attack was not being treated as terrorism but later changed their opinion.
Mental health is being considered a major factor in the incident, a security source said.
Thames Valley Police however said they launched a murder investigation.
They said they arrested a man, 25, at the scene and were not pursuing any other suspects.
The arrested man was a Libyan citizen identified by British media as Khairi Saadallah.
According to multiple international media, the suspected terrorist, Khairi Saadallah converted to Christianity around three years ago.
His cousin, who spoke with The Sun, said, “He started going to church and had tattoos all over his body including one of a cross on his arm.”
One of his neighbours also told Telegraph: “Khairi was very quiet, rarely spoke and wore very Western clothes. Three years ago, Saadallah started dating a British woman who was “very religious” and started going to church.
He converted to Christianity and even got a tattoo of a cross on his arm, according to his cousin.
“He’s not Muslim any more,” she said. “It’s like he’s always been in the UK.”
“This was an atrocity,” said Neil Basu, Britain’s most senior counter-terrorism police officer.
“From our inquiries undertaken so far, officers have found nothing to suggest that there were any other people involved in the attack, and we are not looking for anyone else in relation to this incident.”
Only one of the three victims, teacher James Furlong, has so far been publicly identified.
Two colleagues, Anne Kennedy and Katie Pearce, said Mr Furlong “Truly inspired everyone he taught through his passion for his subject and his dedication”.
