A man arrested by the RCMP in connection with the shooting of a German tourist in Alberta has been released from custody, police say.

The 60-year-old tourist was shot in the head Thursday on Highway 1A near Morley, Alta., about 60 kilometres west of Calgary. He was driving an SUV on the highway at the time, and was rushed to hospital for emergency surgery. He was later listed in critical but stable condition, while his three passengers suffered minor injuries.

Police initially suspected that the shooting was a case of road rage, but later walked that back and said the people in the SUV were not the “intended targets” of the attack.

A man was detained Friday in nearby Cochrane, Alta. Investigators also seized a black car that matched the description of the one involved in the shooting.

The man was later released without being charged, RCMP said Saturday.

“The Cochrane RCMP with Calgary General Investigation Section continue to follow up on leads and are pursuing all avenues,” police said in a statement.

“An update to this investigation will not be provided until the RCMP have confirmed information to relay to the public.”