British Columbia search crews say conditions have been challenging in the hunt for a charter fishing boat that sank in the Strait of Georgia, leaving six missing and presumed drowned.

Richmond RCMP say in a statement that conditions have made the search slower and more difficult but a slack tide when currents are not moving is expected Thursday afternoon, and could provide a better window for teams to work.

CLICK HERE TO LISTEN TO 1130 NEWSRADIO VANCOUVER LIVE!

The RCMP Underwater Recovery Team and West Coast Marine Services are using sonar to search for the charter boat that sank Sunday in what police have called “very deep waters” of between 150 and 180 metres.

Four people were rescued from the water with hypothermia.

The investigation into what happened is being led by the Richmond Serious Crimes Unit.

Corp. Frank Bryson with the Richmond RCMP says in the statement that even after the vessel is found, it could take days to safely investigate, document, and potentially recover it.