A prominent Ugandan opposition politician was kidnapped during a book launch in Kenya over the weekend, transferred to Uganda and is being held at a military jail in Kampala, his wife said on Wednesday.

Kizza Besigye has run against Ugandan President Yoweri Museveni in four elections and lost each time, although he has rejected the results, alleging fraud and voter intimidation. He has been arrested dozens of times before.

The arrest of Dr Besigye comes barely weeks after US government raised concerns about extra-judicial killings, arbitrary arrests and disappearances of anti-government activists in Kenya.

On June1, during Kenya’s Independence Day celebrations in Nairobi, President Yoweri Museveni, accused Kenyan youthful opposition members of parliament of working in cahoots with their Ugandan counterparts to cause turmoil. Museveni’s allegations were, however, were not backed with evidence.

In Kenya, President Museveni has been viewed as President Ruto’s “guardian angel” and mentor.

“I request the (government) of Uganda to release my husband Dr Kizza Besigye from where he is being held immediately,” said his wife Winnie Byanyima.

A spokesman for the Ugandan military could not be immediately reached for a comment.

“As police we don’t have him; so we can’t make any comment,” Ugandan police spokesman Kituuma Rusoke said.

A spokesperson for Kenya’s national police did not immediately respond to a request for comment.

In July, Kenyan authorities detained 36 members of Besigye’s Forum for Democratic Change (FDC) party, one of Uganda’s main opposition groups, and deported them to Uganda where they were charged with terrorism-related offences.

Besigye, who was Museveni’s physician during the guerrilla war but later became an outspoken critic, was kidnapped on Saturday during the launch of a book by veteran Kenyan opposition politician Martha Karua, Byanyima wrote on the social media platform X.

“I am now reliably informed that he is in a military jail in Kampala,” said Byanyima, who is the executive director of UNAIDS, the United Nations programme on HIV/Aids. “We, his family and his lawyers, demand to see him. He is not a soldier. Why is he being held in a military jail?”

Museveni’s government has been accused of repeated human rights abuses against opposition leaders and supporters, including illegal detentions, torture and extra-judicial killings.

Officials deny the accusations and say those arrested are detained legally and processed appropriately by the court system.

• A Tell / Reuters report