Jihadists have reportedly been using social media to encourage lone wolf-style attacks on Israelis at the Rio Olympics.

According to material obtained by the Foreign Desk news website, social media messages from a group backing Al Qaeda urge would-be jihadists to attack athletes from a number of Western countries, including France and the UK.

However, US and Israeli athletes were highlighted as priority targets, with messages stating: “One small knife attack against Americans/Israelis in these places will have bigger media effect than any other attacks anywhere else.”

The posts went on to say: “From amongst the worst enemies, the most famous enemies for general Muslims is [sic] to attack Israelis.”

Security has been heightened in Brazil during the run-up to the Olympics, which are due to start in early August. On Thursday, Brazilian police arrested 10 people and announced that they had broken up a pro-Daesh group planning to launch attacks during the games.

This year will mark 44 years since the Munich massacre, when 11 Israeli athletes were taken hostage and subsequently killed by the Palestinian Black September terrorist group.

In a statement made earlier this year, Andrei Rodriguez, Brazil’s secretary of government security for major events, said that Brazil was planning to use 85,000 security personnel to protect the Olympics, double the number used in London four years ago.