One person died and 25 were injured when a Portuguese train with 47 people on board, many of them tourists, derailed and plunged into a ravine yesterday, officials said.

A spokesman for the civil defence service said 10 people were seriously injured in the accident in the Douro valley region, an area of steep, vine-covered slopes famous for its port wine.

"A derailment of a train with about 50 people has occurred and the train fell into a ravine," the spokesman said.

A local mayor said most of the passengers were tourists.

Two rescue helicopters were flown to the area and about 100 emergency workers were helping in the effort.