Oslo - Three Norwegian coach passengers averted a potential serious accident when they intervened to stop a runaway bus after the driver collapsed, reports said Wednesday.

The bus was travelling at around 100 kph when the driver collapsed. The three passengers managed to drag him out of his seat and stop the vehicle before alerting police and emergency services.

The incident occurred Tuesday night on the E6 highway near Steinkjer, not far from Trondheim, broadcaster NRK reported.

A safety barrier helped keep the bus from slewing into oncoming traffic.

"We hit the barrier while we struggled to get control over the wheel," Gunnar Hamarsland, one of the trio, told NRK, adding it was "lucky" the barrier was in place.

By the time an ambulance arrived, the driver had regained consciousness. (dpa)