The family of a former Surbiton headteacher have paid tribute to an “incredibly brave and courageous person” after she was robbed and murdered in Brazil.

Adventurer Emma Kelty, 43, was kayaking alone in the Brazilian Amazon when she died.

In a statement released by the Foreign Office, her three siblings said she was “dearly loved by us all and her strength will be sorely missed”.

The Londoner had left her job as headteacher at Knollmead Primary School to embark on a 4,000-mile trip from the Amazon's source in Peru, through Brazil and to its mouth on the Atlantic Ocean.

She was using a GPS tool, social media and blogging to let friends follow her progress.

She was last heard from on Wednesday, September 13, days after tweeting that she had seen “50 guys in motor boats with arrows”.

Her last known location was around 150 miles west of the jungle city of Manaus, between the towns of Coari and Codajas.

Head of the Amazonas state homicide division Ivo Martins said after she was killed, her body was thrown in the Solimoes River.

Three people are in custody including a teenager who had confessed to carrying out the killing with six other people.

Ms Kelty's brothers Piers and Giles and her sister Natasha said: “Emma was an active and determined sister who challenged herself, latterly through her adventures on the Pacific Coast Trail, as well as in the South Pole and Amazon River.

“In a world that is today a much smaller place, the explorer in our sister found herself seeking ways to prove that challenges were achievable.

“We are extremely proud of our sister who was dearly loved by us all and her strength will be sorely missed.”

Some of Ms Kelty’s belongings, including the Kayak, were found by the Brazilian Navy on Friday, September 15.

A Foreign Office spokesman said on Tuesday: “We are supporting the family of a British woman following her death in Brazil and are in contact with the Brazilian authorities.”