Some 40 protestors entered a five-star Geneva hotel this week where Cameroon's president was staying and scuffled with his security staff in the lobby, according to police and Swiss media reports.
Geneva police were called to the luxury Intercontinental Hotel shortly after noon (10:00 GMT) on Tuesday, after around 40 protesters had "penetrated into the lobby", spokesman Jean-Philippe Brandt said.
"They were demonstrating against the current government in Cameroon," he said, adding that it had taken about 30 minutes to "re-establish the peace".
According to the Tribune de Geneve daily, the demonstrators were Cameroonian opposition figures living in exile who had come to protest the country's long-time president Paul Biya who was a guest at the hotel.
It said the 86-year-old, who has ruled Cameroon since 1982, had been staying at the hotel since Sunday.
The paper reported that there had been a "fight" between the demonstrators and the president's security personnel, but Brandt said he could not confirm that information.
When contacted, the hotel refused to confirm Biya's presence in the establishment or that the unauthorised demonstration that had taken place there.
Biya's office did tweet on Sunday that the president and his wife had left the country "for a short private stay in Europe."
The Cameroonian embassy in Bern meanwhile voiced concern in a statement over what it said was a planned "violent" demonstration in Geneva next Saturday by Cameroonian nationals living in various European countries "to protest against the presence of the Head of State, His Excellence Paul Biya, in Switzerland."
"The embassy calls on the Cameroonian community in Switzerland and in neighbouring countries to turn their back on such demonstrations, which for some time have been an expression of hatred, violence and tribalism, which are all contrary to patriotism and love of Cameroon."