It happened yesterday tea time, at around 18:00.
The CID is leading the investigation and any witnesses should call it on 725111 or Crimestoppers anonymously on 0800 555 111.
The road was later closed for a while as officers investigated the incident during the evening, with a number of people posting eye witness comments on social media.
One woman commented on the Guernsey Police Facebook page that the road was closed at both ends while others were asking what had happened.
Pictured top: Le Grand Bouet road, where last night’s reported incident happened.