LISBON (AFP) - A light plane made an emergency landing on a packed beach near Lisbon on Wednesday (Aug 2), killing a man and an eight-year-old girl who were sunbathing, authorities said.

Hundreds of people were on the Sao Joao de Caparica beach about 20km south of Lisbon at the time and witnesses told cable news station SIC Noticias people ran to avoid the plane.

"A plane with two people on board made an emergency landing on Sao Joao da Caparica beach, striking two sunbathers and causing their deaths," the National Maritime Authority said in a statement.

The two pilots of the plane were not injured and are being questioned, a spokesman for the authority told AFP.

The dead man was 56 years old and the girl just eight, an emergency services official said.

The small aircraft, reportedly a Cessna, made little noise as it skimmed low over the sunbathers, witnesses told Portuguese media.