A terrorist attack targeting the French delegation at the Rio 2016 Olympics has been foiled by security services, it has emerged.

The head of French military intelligence said “partner agencies” had issued an alert about the alleged plot by a Brazilian Islamist militant, according to a report into the Paris terror attacks in January and November, which killed 147.

No other details about the plans were released and the information was not shared with Brazil’s intelligence agency Abin.

A spokesman for Brazil’s institutional security cabinet, which oversees the country’s information services, told AFP: “We were not the source of information and the Brazilian intelligence agency (Abin) was not officially informed either of this matter.”

The French inquiry report was published as security services in Rio de Janeiro prepared to stage a simulated attack this weekend to test counter-terrorism response plans.

Some 500 officers, troops and first responders will be involved in the exercise at Deodoro station near one of the venue clusters in the north of the city on Saturday.

Earlier this month, Alexandre Moraes, justice minister, said a terror attack during the Olympics was a “possibility” but not a “probability”.