Pedro Sanchez, who had been filming a swollen river with his mobile phone, said he escaped through the window of his auto and swam to safety after the waters rose two metres in 30 seconds, engulfing his vehicle.
Spain's weather agency said up to 22 centimeters (8.7 inches) of rain fell within four hours, triggering flash floods in the island.
People clean the mud from their houses in Sant Llorenc, the town hardest hit by the downpours located 60 kilometers (40 miles) east of Mallorca's capital, Palma, Spain, on Wednesday, Oct. 10, 2018.
A Balearic Islands' emergency services spokeswoman, who wasn't authorized to be named in media reports, told The Associated Press that the body of a Dutch woman was also recovered from the garage of a house in Arta, another nearby town.
Antonia Bauza, the deputy mayor of Sant Llorenc, confirmed two of the victims were British nationals.
There is also one unidentified man - also possibly a foreigner.
Military divers found the couple's bodies still inside, while Mr Sillero was later found lifeless nearby, the paper said.
A Foreign Office spokesman said: "We are supporting the family of two British people following their deaths in Spain, and will do all we can to assist them at this deeply hard time".
WITH the death toll following the flash flooding in Mallorca already standing at ten, emergency services are concentrating their efforts to find a child and two Germans who are still unaccounted for.
Last year, 13.8 million foreign tourists visited the Balearic Islands led by German nationals and then Britons, according to official statistics.
The flooding forced schools to close and displaced people to shelter in sports halls.
"My honest condolences to the relatives of the deceased and injured by the severe floods in San Llorenc".
Spain's Prime Minister Pedro Sanchez and members of Parliament hold a minute of silence for the victims of heavy rains in the Spanish island of Mallorca at the start of a parliamentary session in Madrid, Spain, October 10, 2018.
The regional government declared three days of mourning.
He promised financial help for affected zones.