A collision between a train and a school bus at a level crossing in the small Belgian town of Buggenhout on Tuesday morning killed four people and injured five children.”This is one of the worst accidents in the history of Belgium at a level crossing,” Thomas Baeken, spokesperson of the Belgium Railway Infrastructure Manager Infrabel, said.Nine passengers were aboard the minivan, including seven children and two adults. The bus was heading to a school for children who have specific needs in Buggenhout.”Unfortunately, there are two children who lost their lives, a 12-year-old and a 15-year old. The driver and the assistant also lost their lives,” Federal police spokesperson An Berger told Euronews.The injured were taken to the hospital and their lives are not at risk, she stressed.About a hundred passengers were aboard the train. All of them were evacuated and none were injured, Dimitri Temmerman, spokesperson for the National Railway Company of Belgium (SNCB), said.’The barriers were down’An investigation has been open to help clarify the circumstances of the tragedy.”At the moment of impact the level crossing was closed, so that means the lights were on red and the barriers were down,” Thomas Baeken said. “Why does the chauffeur still proceed? We don’t know.”The train that was coming from Bruges and heading towards Mechelen was speeding at 90 kilometres an hour at the moment of impact around 8.15AM, according to Infrabel.It was slowing down as it was approaching the Buggenhout train station a few hundred meters away.The train driver attempted an emergency brake but could not avoid the crash.”The level crossing was already closed quite some time before the car was driving onto the level crossing. But the impact was almost instantaneously because the train was already really close to the level crossing and there was no time to stop,” Baeken said.The bus was catapulted into a pole before crashing in front of a house a few meters away.20 accidents last yearAccidents at level crossings in Belgium are decreasing, according to Infrabel, with around 20 incidents reported last year. The latest accident at this particular level crossing occurred in 2007, it said.Belgium has almost 1,600 level crossings, equipped with different safety systems depending on location and traffic conditions.”Each level crossing has a safety equipment that is decided by Infrabel and also by the government”, Baeken told Euronews.”Here, it can be said that the crossing is equipped with two barriers, four lights and a sound and a bell signal.”Equipment norms at level crossings differ across the EU.”Each country can decide the type of equipment. In Belgium, we decided to install two red lights with one white light. For example, in France, there is only one red light and there is no white light,” Vincent Godeau, Infrabel security advisor, told Euronews.Yet, some standard traffic rules apply. The 1968 Vienna Convention on Road Traffic established that drivers must stop at a red light and that the St Andrew’s cross serves as the international symbol for a railway level crossing without gates or barriers.