Ugandan police have detained a lawmaker, and close ally of opposition leader Bobi Wine, for his alleged role in election-related violence last week.

Muwanga Kivumbi, a deputy leader of Wine's National Unity Platform (NUP), is accused of organising attacks on a police station and a vote-tallying centre after their electoral loss, which the party denies.

The police have said that seven people were killed in the incident, but the politician has given a different account, saying that 10 people were killed at his home as they waited for parliamentary election results.

The Uganda Police Force said in a post on X on Thursday that Kivumbi would be "arraigned before court in due course".

"His arrest is in connection with recent incidents of political violence," it added.

Kivumbi's arrest follows tensions after last week's elections in which President Yoweri Museveni was re-elected for a seventh term.

During his victory speech over the weekend, Museveni warned opposition figures including Kivumbi of coordinated plans to attack polling stations.

He said seven people were shot dead by police after groups of alleged opposition supporters, armed with machetes, attempted to carry out violent attacks in Butambala district outside the capital, Kampala.

Wine, Museveni's closest challenger and who is in hiding after fleeing a raid on his house after the elections, has denounced the results as "fake", citing electoral fraud.

He has also alleged that there was "silent massacre" under way and a crackdown targeting political activists.

On Tuesday, he posted on social media that more than 100 people had been killed in election violence, without stating evidence.

This came after Uganda's army chief Gen Muhoozi Kainerugaba, who is also Museveni's son and his potential successor, said the security forces had killed 22 opposition supporters during poll-related violence.

Since the election, Ugandan authorities have reportedly arrested dozens of youths on various charges linked to election-related incidents in Kampala.

Museveni first came to power as a rebel leader in 1986. He will have served for 45 years when the next term ends in 2031.

Uganda has not witnessed a peaceful transfer of presidential power since independence.