Cairo - Egypt's world javelin silver medallist Ihab Abdelrahman has been barred from the Rio Games by his national Olympic Committee on Tuesday after testing positive for banned substances.
Abdelrahman, who won silver in last year's world championships in Beijing, had been asked to travel to Barcelona, where his tests were analysed, for a second one to confirm the results.
The 27-year-old refused, demanding a new test take place after the Rio Games which get underway on August 5.
Another athlete, hammer thrower Mostafa Al-Gamel, will also miss the Games because of injury.
"They have both been excluded," Mamduh al-Shishtawi, the executive director of the Egyptian Olympics Committee, told AFP.
Doping has been to the forefront of the run-up to the Summer Games with Russia's participation already under fierce scrutiny over state-sponsored doping.