Detectives from Hertfordshire Police are urgently seeking to trace 22-year-old Jack Wall in connection with the disappearance of Amelia Arnold, who was last seen on Wednesday.
Wall, of Hadrian's Walk, Stevenage, has been urged to hand himself in to police, who have also issued an appeal for sightings of a Citroen Berlingo van as part of their inquiry.
More top news
Hundreds of people have gathered in central Belfast to show their opposition to Brexit.
Emergency services were called to reports of a collision on the northern end of White Horse Vale at 2.20pm on Saturday.
A flight to Glasgow had to be abandoned after the plane flew into a flock of birds at 1,500ft.