An investigation is underway in Slovakia after a bus collided with a train, killing at least 11 people.Some reports put the death toll at 13. Around 20 victims were taken to hospital, some with serious injuries. The accident happened near the central town of Brezno. The passenger train smashed into the bus at a level crossing. An official said there were only light signals there, with no barriers to stop vehicles from passing. All those who died were on board the bus which, it is believed, was taking people on a skiing trip.