Swiss police have come under fire by Amnesty International for using excessive force against asylum seekers.
The human rights organisation said black Africans and Muslims in particular were treated harshly by police officers.
In its 2003 report, Amnesty cited a handful of cases in which violence was used against non-Swiss people - and said this had in some instances even resulted in death.
Jürg Keller from Amnesty's Swiss section told swissinfo there had been "three or four cases where people have died because of these methods".
Keller added that Switzerland had tried to clamp down on these practices in the last two years - but there was still a long way to go.
"We try to speak to police departments both in different cantons and on a national level, but we still have these cases," he explained. "It seems to be very difficult to change the methods used by the police."
The report singled out police methods such as the use of sedatives and physical restraints on asylum seekers during forced deportation, including in airports.
It said the unauthorised use of medication to subdue asylum seekers contravened Swiss and international guidelines on medical ethics.
Keller pointed to an incident in 2001 when Samson Chukwu, a Nigerian asylum seeker living in canton Valais, died from suffocation after police sat on him to restrain him.
A Valais court later dismissed a lawsuit filed by Chukwu's family against the police officials concerned.
"The officers were released because they argued that they didn't know this method was so dangerous," Keller explained.
A similar explanation was given by police officers in canton Bern last year, when they were questioned in court about the death of a Kurdish asylum seeker, Cemal Gömec.
The report states that it is not just adult asylum seekers who bear the brunt of police violence in Switzerland - children of non-Swiss origins have also been mistreated.
Earlier this year, a court in Geneva found a policeman guilty of bodily assault after he set his dog on a 14-year-old asylum seeker from Kosovo, the report said.
Keller says the onus to stamp out these practices lies on the cantonal police forces, especially as executing deportation orders falls within their remit.
"It's really the responsibility of the police in the cantons to change the attitudes of their officers, so that they change their methods and their behaviour," Keller emphasised.
The Swiss Federal Police Office declined to comment on Amnesty's findings when contacted by swissinfo, saying the allegations concerned cantonal police forces.
swissinfo, Faryal Mirza
Amnesty International has criticised the use of excessive force by the Swiss police in its 2003 report.
It cites cases where methods used to restrain asylum seekers have led to their deaths.
Despite discussions with police forces, Amnesty says it is difficult to change policing methods.