A migrant who stowed away on a truck in the Channel Tunnel was found dead on Tuesday, disrupting travel between France and England for a third week in a row, police and the tunnel operator said.

The reported death Tuesday came shortly after Eurotunnel reported a group of migrants was found on a truck in the tunnel leading from Calais in northern France. Thousands of migrants are camped in Calais, living in dire conditions as they hope to reach a better life in Britain by stowing away on trucks as they wait to be loaded onto freight trains for the trip.

The encampments have heightened tensions between France and Britain, with each accusing the other of failing to deal with the situation.

The local prefecture confirmed the death but offered no details. Eurotunnel said border police responding to the report of stowaways found the dead migrant. Train service was delayed for thousands of passengers as well as on the freight trains that carry trucks between France and England.