stabbing in Reading on Saturday which left three people dead and three more seriously injured has been declared a terrorist incident, police have confirmed.Three people were killed and three more are still in hospital following the mass stabbing at Forbury Gardens, in Reading, Berkshire.A 25-year-old man who was arrested on suspicion of murder last night, remains in police custody at this time.The suspect is a Libyan asylum seeker and mental health is being considered a major factor in the incident, a security source has told the PA news agency.Officers from Counter Terrorism Policing South East (CTPSE) have been working closely with Thames Valley Police’s Major Crime Department throughout the night.Deputy Assistant Commissioner Dean.