Kampala (AFP) - Leading Ugandan opposition figure Kizza Besigye is being held in a military jail after being “kidnapped” in Kenya, according to his wife, a top UN official.

Winnie Byanyima, head of UNAIDS, demanded on X in a post early Wednesday that the government of Uganda “release my husband Dr. Kizza Besigye from where he is being held immediately”.

The Ugandan authorities – who said they were looking into the reports of Besigye’s disappearance – have been waging a crackdown on the opposition in recent months, arresting prominent leaders and putting members of opposition parties on trial.

Besigye “was kidnapped last Saturday while he was in Nairobi” to attend a book launch by Kenyan opposition politician Martha Karua, Byanyima said.

“I am now reliably informed that he is in a military jail in Kampala,” Byanyima said of her 68-year-old husband who is a medical doctor.

“We his family and his lawyers demand to see him.”

Besigye, an ally turned foe of Uganda’s iron-fisted veteran President Yoweri Museveni, has tried unsuccessfully several times since 2001 to unseat him in presidential elections and has often been targeted by the authorities.

“We are cross-checking the information about the reports of Besigye’s alleged disappearance and at the moment we can’t confirm his whereabouts,” Ugandan government spokesman Chris Baryomunsi told AFP.

“We are in touch with the security agencies here and in Kenya to get the correct information,” he added.

In July this year, 36 members of the Forum for Democratic Change (FDC) – the party Besigye founded two decades ago – were deported from neighbouring Kenya and put on trial in Uganda on terrorism charges.

They were freed on bail last month.

- ‘Kenya used to be safe haven’ -

After their arrest, Besigye denounced the “junta” in power and claimed that the 36 “were illegally detained and sneaked back from Kenya”.

Bobi Wine, another prominent opposition leader who has frequently found himself targeted by the authorities, called for Besigye’s immediate and unconditional release.

“It is very shocking that Kenya which used to be a safer haven for (Ugandan) dissidents is now increasingly becoming an operational zone for the dictatorship in Uganda,” he said on X.

Besigye has broken away from the FDC, forming a new party earlier this year called the People’s Front for Freedom (PFF).

Phillip Wafula Oguttu, a leading figure in the new party who was also in the FDC, said the disappearance of Besigye was “not surprising” following the alleged abduction of the opposition party members in Kenya.

“We have been trying to reach out to him but his phone is inaccessible since Saturday,” he told AFP, adding that the Nairobi hotel where Besigye was staying had not seen him since he checked in.

“Our conclusion is this is a confirmed case of abduction,” he added. “We pray where ever he is, he is safe.”

- Bush war allies -

Museveni and Besigye were once close. They fought together in the bush war to overthrow Milton Obote, during which time Besigye served as Museveni’s trusted personal physician.

The two men eventually became political foes when Besigye broke ranks with the ruling National Resistance Movement to make a bid for the presidency in 2001, and later formed the FDC with other disaffected NRM members.

Besigye and other former Museveni allies have also fallen out of favour with the president over the rapid elevation of the “first son” Muhoozi Kainerugaba, who is now head of the Ugandan defence forces.

Besigye married Byanyima, who was previously romantically linked to Museveni, in 1999.

In the past, Besigye has faced accusations of treason and rape, frequent arrests and detentions, regular tear-gassings – both of him and his supporters – beatings and harassment.

Concerns have been mounting recently about Kenya’s involvement in reported kidnappings of foreign nationals.

Last month, Nairobi repatriated four Turkish refugees who rights groups say were abducted and forcibly returned in violation of international law.

It followed media reports that they had been kidnapped on the street in the Kenyan capital along with three others who were later released.

Turkish agents also abducted the leader of the Kurdistan Workers’ Party (PKK), Abdullah Ocalan, in Kenya in 1999 after years on the run.