Hakainde Hichilema has been arrested on treason charges after allegedly refusing to allow the presidential motorcade to pass down a street. Hichilema contested last year’s election results after a narrow defeat.

The leader of Zambia’s United Party for National Development (UPND), Hakainde Hichilema was arrested Tuesday on charges of treason after he obstructed a presidential motorcade for President Edgar Lungu.

Treason is a non-bailable offence in Zambia, with a minimum jail term of 15 years and a maximum sentence of death.

Authorities say Hichilema blocked Lungu’s motorcade with his own vehicles during a traditional ceremony in Zambia’s Western Province over the weekend. Hichilema’s motorcade refused to yield to Lungu’s motorcade after Presidential security details signaled for Hichilema’s motorcade to move out of the way, according to authorities.

Hichilema was detained following an early morning raid on his house in a Lusaka suburb on Tuesday.

More than a hundred armed police surrounded Hichilema’s house and used tear gas in the operation to arrest him. Police did not say why they arrested the opposition leader but spokeswoman Esther Mwaata Katongo said Hichilema “will remain in detention.”