A five-year-old British girl and her grandfather have drowned in rough seas at a Portuguese beach, it has been reported.

The Foreign Office is in touch with local authorities following claims of the fatalities at the tourist resort of Nazari, about 60 miles north of Lisbon.

It is understood they were swept away by waves along with the girl's grandmother as the child's parents were left helpless on the shoreline, around 2pm yesterday.

The three victims were spotted by fishermen "who pulled them from the waves and called rescue services".

Police, firefighters and paramedics gave first aid to the grandmother and she is in a stable condition in hospital. The parents have been treated for shock.

A report said the 66-year-old grandfather drowned while trying to save the girl's life, but details have yet to be confirmed.

Albuquerque e Silva, commander at Nazari Port Authority, said: "The grandfather was dead when he was hauled from the water.

"Emergency services attempted to resuscitate the child, but to no avail.

"The two victims, accompanied by the grand- mother, went on a stroll away from the Salgado beach, which is under lifeguard surveillance.

"It must have been during this period they were knocked over and dragged in by the waves."

The identities of the family members have not been released.

A Foreign Office spokesman said: "We are aware of reports of the deaths of two British nationals in Portugal and we are in touch with the local authorities."