Sussex Police say inquiries into the circumstances of the collision are ongoing.
Motorists are urged to avoid the area following the incident in Findon, West Sussex.
Mick and Carol Maidment say they were not told the dog they rehomed had bitten its previous owner.
The family of Jakub Ziomko, reported missing from the Portlethen area on 8 February, have been made aware.
A coastguard helicopter, lifeboat and search teams were called into the search in the Portlethen area.
UK arrivals from France express shock at home visits by officials despite the easing of Covid rules.
