Swiss police fired water cannon, tear gas and stun grenades at Cameroonian protesters outside UN headquarters in Geneva on Saturday as the crowd surged towards a luxury hotel hosting Cameroon's president.
About 250 demonstrators demanding an end to President Paul Biya's rule squared off with dozens of police, many in riot gear, backed up by armoured vehicles.
The standoff turned violent when the crowd, many draped in Cameroon flags, started making its way towards Biya's hotel, about 500 metres (1,600 feet) from a square outside the UN where they had gathered.
An AFP reporter witnessed police beating and kicking a protester on the ground.
Cameroonian nationals living in various European countries clash with riot police in Geneva. Fabrice Coffrini/AFP
Biya, 86, "has run his dictatorship for nearly half a century," said rally co-organiser Robert Wanto, a Cameroonian national who has lived in exile for three decades.
"We are here to demand that Cameroon be allowed to enter the modern democratic era," he told AFP outside of the UN's European headquarters ahead of the protest.
Several hours before the rally started, about 30 protestors set up a stage with banners and graphic pictures of dead bodies apparently mangled by torture, with the message: "The people say no to Paul Biya".
Cameroon's embassy in Bern warned earlier this week that Cameroonian nationals living in various European countries were planning a "violent" protest against Biya on Saturday.
Geneva police told AFP it was expecting a "large" demonstration. Authorisation was granted but limited to the square outside the UN.
'Ultimatum'
They were not granted permission to march to the five-star Intercontinental Hotel where Biya is believed to have been staying since Sunday.
But Wanto told AFP the demonstrators had given Biya an "ultimatum" to leave and if he remained at the hotel when the protest began, "we will march there".
He pointed out that Biya had made it a habit to stay at the pricy Intercontinental during long visits to Switzerland, where he reportedly comes for medical treatment.
"He thinks it is OK to come here and spend billions of our money when our country is economically sick," Wanto said.
Cameroonian nationals demonstrate against the presence of Cameroon President in Geneva. Fabrice Coffrini/AFP
Early Saturday, dozens of suit-clad men believed to be part of the president's security detail stood around the hotel.
Several police vans were also parked outside the hotel and groups of officers had been stationed at regular intervals between the tall glass building and the UN square.
Over the past week, there have already been several scuffles with small numbers of demonstrators outside the hotel and even inside the lobby.
An attack on a Swiss journalist covering the events by men believed to be Biya's security staff sparked a diplomatic incident, prompting the Swiss government to summon Cameroon's ambassador in Bern on Thursday.
"The dictator must be senile to want to transport the violence he unleashes on his country on a daily basis to the soil of a democratic country," Wanto said.
Cameroon, a former French colony, has faced a succession of crises and is wracked by a deadly conflict between separatists and government forces in its English-speaking west.
Opposition leaders have faced mass arrests, and rights groups claim detainees are tortured and many disappear.
Agence France-Presse