A police investigation was unable to reveal the tragic final movements of an escaped hospital patient who died on the A47 more than 20 miles away.
Southern Hill hospital patient Lee West left the Mundesley facility after "tailgating" through an unlocked gate behind a nurse.
Less than two hours later he was seen walking in the middle of the dual carriageway at Postwick, where he died after being hit by two separate vehicles.
An inquest into his death is due to conclude this week. During proceedings so far evidence has been given about his escape from the hospital, where he was sectioned under the mental health act, and the crash that ultimately killed him.
However, the court has heard that the two hours between his departure and the crash continue to be a mystery, despite subsequent police investigations.
Mark Easter, a civilian road deaths investigator for Norfolk Constabulary, told the court his probe had been unable to ascertain how Mr West travelled the 22 miles from the hospital to the A47 at Postwick, where the crash occurred.
He said: "My first thought was that he had gone by taxi and made enquiries with seven taxi firms in the area, but all seven said they had not given Lee West a lift that night.
"We also made an appeal through the local press asking whether anybody had given him a lift, but nobody came forward."
The investigator added that police were unable to extract any clues from Mr West's mobile phone, due to it being PIN protected.
The court heard Mr West had left the hospital shortly after 8pm, with the next likely sighting of him coming at 9.35pm, when a member of public reported a man being seen walking on the NDR near Broadland Business Park.
Police officers attended the scene, but were unable to locate anybody.
Then, at 9.46pm, police received a report of a man walking on the A47 near Postwick, where the crash happened just three minutes later.
The inquest continues.
Do you need support? Samaritans can be reached at all hours via 116 123.
Comments: Our rules
We want our comments to be a lively and valuable part of our community - a place where readers can debate and engage with the most important local issues. The ability to comment on our stories is a privilege, not a right, however, and that privilege may be withdrawn if it is abused or misused.
Please report any comments that break our rules.
Read the rules here