Home Secretary Priti Patel explains why the terror threat level has been heightened.
An explosion outside Liverpool Women's Hospital on Remembrance Sunday has been declared a terror incident by police - and has seen the UK terror threat be raised from substantial to severe.
A taxi exploded and was engulfed in flames just before 11:00 GMT at a drop-off zone near the entrance, killing the passenger and injuring the driver.
Home Secretary Priti Patel explained why the UK terror threat level has been heightened.