THE HAGUE, Netherlands — A car struck a group of cyclists who were on a school camping trip, killing three children and an adult on Thursday in the rural southern Netherlands, emergency services said.

Police said in a statement that they detained a 19-year-old man and were investigating his involvement. They didn’t say if he was the driver of the car.

Two children and an adult died at the scene. Four children were seriously injured and were taken to hospitals in the Netherlands and nearby Belgium for treatment. One of them died Thursday evening at a hospital in Rotterdam, the Zeeland Security Region organization said in a statement.

Those who were killed and injured were part of a group of 14 schoolchildren and two chaperones from an elementary school in the nearby town of Axel.

Police are investigating the cause of the incident on a provincial road that runs between farmers’ fields near the small town of Vogelwaarde, about 200 kilometers (125 miles) south of Amsterdam. A photo displayed on Dutch media showed a car, with its windshield smashed and hood damaged, in a field next to the road.

Such incidents involving multiple cyclists are rare in the Netherlands, where bicycle riding is woven into everyday life and almost all roads have dedicated cycle lanes. No further details were immediately available.