“They beat me, punched me and kicked me with their boots. No part of my body was spared,” he said from the United States where he is seeking medical treatment for injuries he claimed were sustained during his arrest and detention.

“They wrapped me in a thick piece of cloth and bundled me into a vehicle,” he wrote of his arrest in the northwestern town of Arua.

“Those guys did to me unspeakable things in that vehicle! They pulled my manhood and squeezed my testicles while punching me with objects I didn’t see,” Kyagulanyi said, adding the officers stole his wallet and phone before knocking him unconscious.

Kyagulanyi, who was charged with treason last week and released on bail, was rearrested while trying to leave the country to seek medical treatment. He was subsequently allowed to depart.

The young MP has become a lightning rod for opposition to the long rule of the country’s 74-year-old president who critics say is out of touch with a youthful population.

His case has drawn international attention with scores of musicians, activists and politicians signing an open letter condemning his treatment by the government.

Monday’s 3,500 word Facebook post was Kyagulanyi’s first public statement since his arrest.

“I was shocked on how they tried to play down the atrocities committed by security agencies on innocent citizens,” he said.