A major investigation was launched earlier this month when human remains were found in the car. A shotgun was also discovered inside the vehicle.
This week it was confirmed that the remains were those of 33-year-old Mikus Alps, who disappeared several hours before the car was found.
An investigation into the cause of death is continuing, and a handwriting expert is analysing a ‘sombre and reflective’ letter purporting to be from Mr Alps which was handed into the police after the investigation was launched.
In a statement, Guernsey police said: ‘We have received support from two senior investigators from the States of Jersey Police, who have worked alongside our senior management to review the numerous lines of inquiries undertaken.
‘This sort of collaboration is common practice among police services when dealing with a critical incident.’
