The Kristiansand-to-Oslo express had been due to pass through Hjuksebø, but was delayed, and the shunter believed he had time to turn a waiting freight-train around before it arrived, by shunting a number of freight cars out of the way.
As he had failed to attach them to the engine, however, the cars ran downhill towards Holtsås station, straight into the express, killing fourteen.
The engine of train 5443 was detached from its carriages and pushed the freight cars ahead of it southwards with the intention of pulling them back in on track 3, ready for the return journey.
The shunter made a desperate attempt to run and catch up with the runaway cars, hoping to jump on it and engage the emergency brake.
The station master at Hjuksebø realised the impending danger and called down to Holtsås hoping to stop the incoming passenger train no.
The leading freight car in the runaway was loaded with wooden logs for setting up telegraph poles, and this added to the damage.
[1][2] Men from Norsk Hydro at Notodden were sent to the wreckage site with burners who could cut the trapped passengers away from the mangled train.
Although there were calls for disciplinary action against the shunter, the investigation revealed that other people involved were also at fault, as well as the prevailing routines followed at Hjuksebø station at the time.
There were demands that the Norwegian State Railways compensate the survivors of the Hjuksebø disaster victims, and the injured passengers.