Seven students drowned in eastern Mexico after their vehicle was dragged into a fast-flowing river as they tried to retrieve a boat from its waters, local government sources said Sunday.

The victims, all between 21 and 23 years old, on Saturday were celebrating the end of the school year and summer holidays at a private residence on the banks of the river in the city of Coatzacoalcos.

They were in a pickup truck that they were using to try to pull a boat from the Calzadas-Coatzacoalcos river, sources from the municipal police and emergency services told AFP on condition of anonymity.

The turbulent waters, strengthened by a storm, dragged the vehicle in.

The victims are "five women and two men. They all knew each other," said the source with the emergency services.

An AFP reporter at the scene said the intense storm had complicated efforts to retrieve the victims' bodies.