Veteran Ugandan opposition figure Kizza Besigye appeared in a military court in Kampala on Wednesday, accused of seeking to compromise national security, after his reported abduction in neighbouring Kenya at the weekend.

The manner of Besigye's detention has caused an uproar, with concerns over Kenya's role and the heightened government crackdown on Uganda's opposition.

Besigye, 68, a medical doctor and longtime critic of President Yoweri Museveni, was brought to the General Court Martial in the Ugandan capital under a heavily armed military escort.Standard Group products

He appeared in the dock with another opposition figure, Hajji Lutale Kamulegeya, who was also snatched in Nairobi, his lawyer Erias Lukwago told AFP.

The prosecution alleges they were in possession of two pistols and had "solicited logistical support in Uganda, Greece and other countries with the aim of compromising the country's national security", Lukwago said.

"He has denied the charges and challenged the court's jurisdiction to try him and he has been remanded to Luzira prison until December 2."

Besigye, a retired army colonel, insisted that he was now a civilian and should not be tried in a military tribunal.

Once Museveni's personal physician only to fall out with the president, Besigye has run unsuccessfully against him in elections four times since 2001 and been repeatedly targeted by the regime.

His wife Winnie Byanyima, executive director of UNAIDS, the United Nations Programme on HIV and AIDS, said on X that her husband was kidnapped Saturday while in Nairobi for a book launch by Kenyan opposition politician Martha Karua.

In recent months, the Ugandan authorities have waged a crackdown on the opposition, arresting prominent leaders and putting dozens of people on trial.

In July, 36 members of the Forum for Democratic Change (FDC) -- the party Besigye founded two decades ago -- were deported from Kenya and tried in Uganda on terrorism charges.

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

Besigye recently broke from the FDC, forming a new party called the People's Front for Freedom (PFF), of which his co-accused is also a member.

Ugandan government spokesman Chris Baryomunsi sought to justify the arrests, telling reporters: "You can be arrested from anywhere because countries have treaties or instruments that they signed between them that allow for extradition.

"So being arrested from Kenya would not be a problem," he added.

Rights groups are increasingly concerned that Kenya is colluding in the kidnapping of foreign nationals on its soil.

Last month, the Kenyan government admitted that four Turkish refugees had been repatriated to Turkey following reports they were abducted and forcibly returned without due process.

The Law Society of Kenya said "we strongly condemn" Besigye's arrest, saying it was "against not only our local but also international laws".

Bobi Wine, another prominent Ugandan opposition leader and former presidential candidate who has been arrested multiple times, also voiced outrage.

"We condemn this blatant abuse of the law by the regime here in Uganda, and sadly the authorities in Kenya," he said in a post on X.

"We are back to the dark days when Ugandans were casually picked from the streets of Nairobi and returned to Uganda to be tortured, jailed and others executed."

Museveni and Besigye were once close, fighting together in the 1980s bush war to overthrow Milton Obote, with Besigye serving as Museveni's trusted personal physician.

They became foes when Besigye broke ranks with the ruling National Resistance Movement and ran for the presidency in 2001, later forming the FDC with other disaffected NRM members.

Lately, the opposition has been concerned about the meteoric rise of Museveni's son Muhoozi Kainerugaba, who is now head of Uganda's defence forces.

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

Over the years, Besigye has faced multiple arrests and spurious charges including rape and treason, while he and his supporters have often been teargassed, beaten and harassed.