Tripoli is turning up the pressure on Switzerland again, in the wake of last summer's arrest of one of the sons of Libyan leader Moammar Gaddafi.
Hannibal Gaddafi and his wife, along with the Libyan state, filed a civil lawsuit against the Geneva authorities in a Geneva court on Wednesday.
They are claiming damages for the "disproportionate" way in which they were treated by the Geneva police who detained them in their hotel in July, after receiving complaints that they had seriously mistreated two of their servants.
The couple were released on bail after two days, and charges against them were dropped in September after the servants withdrew their complaint, having reached a financial arrangement with Hannibal.
"Police did not hesitate to use physical force and act with brutality despite a lack of resistance" and along with the justice authorities "deliberately chose to inflict on Mr Gaddafi the most humiliating treatment possible", Swiss television TSR quoted the complaint as saying.
The claimants also say that the Geneva authorities had not complied with the Vienna Convention on diplomatic standards and had set an "astronomical" bail of SFr500,000 ($435,000).
They further claim that police had refused to act on a complaint of theft made by the Gaddafi couple.
The Swiss lawyer for the Gaddafi couple said they were claiming SFr50,000 ($43,000) in moral compensation and SFr470,00 in material damages.
Lars Knuchel, spokesman for the Swiss foreign ministry, said: "The case has been filed with the Geneva courts and it is a good thing." The authorities in Geneva have consistently backed the actions of their police.
Relations between the two countries have been strained ever since the arrest, with Libya taking a number of retaliatory measures against Switzerland.
Libya demanded an apology for the arrest and imposed economic measures against Switzerland, including closing Swiss companies and stopping flights.
Two Swiss nationals working in Libya were also arrested and later released but were refused permission to leave the North African country. The foreign ministry says one of them is unwell and has appealed to the Libyan government to allow the citizens to leave the country on humanitarian reasons.
Bern has ruled out an apology over the affair and stressed the Geneva authorities acted within the law. In a briefing on Tuesday, the foreign ministry noted it could take "a long time" before the crisis with Libya was resolved.
Foreign Minister Micheline Calmy-Rey added that dialogue was continuing but the matter was now between the Geneva authorities and Libya.
Swiss President Hans-Rudolf Merz meanwhile described the 63-page claim as another "stage in a game begun by Libya" and which looked set to continue.
"Every avenue is blocked. I don't see a way out at the moment," he said.
swissinfo with agencies
The Gaddafi case
July 15, 2008: Hannibal Gaddafi and his wife Aline are arrested at a Geneva hotel after police receive reports that they have mistreated two servants.
July 17: After two nights in detention, the couple are charged with inflicting physical injuries and using threats and force against the servants. They are released on bail and leave Switzerland.
July 19: Two Swiss nationals are arrested in Libya. Swiss businesses are forced to close their offices and the number of Swiss flights to Tripoli is cut.
July 23: Libya threatens to stop crude oil deliveries to Switzerland. Bern forms a task force and sends a delegation to Libya.
July 29: Two Swiss nationals arrested in Libya are released from jail.
August 13-16: A Libyan delegation arrives in Switzerland for talks.
September 2: The servants withdraw their complaint after reaching a financial arrangement with Hannibal, ending the legal process.
October 10-12: Reports say Libya is to stop oil deliveries and withdraw its deposits in Swiss banks, but it is later denied. Libya cuts its own airline's flights to Switzerland.
December 15: Swiss International Air Lines can no longer fly to Tripoli "for technical reasons".
January 31, 2009: Talks are held with Seif al-Islam Gaddafi, one of the Libyan ruler's sons, at the World Economic Forum in Davos.
January 25: A diplomatic delegation travels to Tripoli.
March 23: Italy offers to play a mediator role.
April 8: Hannibal and his wife, along with the Libyan state, file a civil lawsuit against the Geneva authorities in a Geneva court.
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