A total of six people were killed when a lorry crashed into a neighbourhood party near the Dutch city of Rotterdam, according to police on Sunday.
Seven others were injured in the Saturday incident, public broadcaster NOS and the news agency ANP reported, citing the police.
Initial reports had said at least three people died, dpa news agency reported.
The truck ran off a dyke and slammed into the Nieuw-Beijerland village near Rotterdam, where people were holding a barbecue.
The vehicle belonged to a Spanish haulage company.
The 46-year-old Spanish truck driver was arrested. NOS reported that he was being investigated for causing a fatal accident. The man, who was not injured, had not drunk any alcohol.
Overnight, rescue crews used a crane to recover the heavy truck and the deceased buried by the vehicle.
Investigations into the cause of the accident were still ongoing.