Rose Kabuye was detained on her arrival at Frankfurt
Rwanda's foreign minister has condemned the arrest of a senior Rwandan official in Germany in connection with a killing that triggered the 1994 genocide.
Rosemary Museminali told the BBC that the arrest of Rose Kabuye, chief of protocol for Rwandan President Paul Kagame, was "illegal and flawed".
Ms Kabuye was detained in Frankfurt on a warrant issued by a French judge.
She is one of nine senior officials wanted over the shooting down of former President Juvenal Habyarimana's plane.
All are members of the party which ousted the genocidal regime.
Rwanda's foreign minister said Germany had no right to arrest Ms Kabuye.
"The whole system which the arrest warrants were based on was flawed, it was based on politically motivated information," she told the BBC's Network Africa programme.
Correspondents say Ms Kabuye, a former guerrilla fighter with the Rwandan Patriotic Front (RPF), now Rwanda's ruling party, has heroic status in Rwanda.
She has since served as an MP and mayor of the capital Kigali, and is one of President Kagame's closest aides.
The plane carrying Habyarimana, a Hutu, was shot down on 6 April 1994, as Mr Kagame's Tutsi rebels were advancing on Kigali.
The Hutu extremist government accused the RPF of the assassination. Within hours, militias set up roadblocks and started to systematically murder any Tutsis or moderate Hutus they could find.
The RPF has always accused the Hutu extremists of shooting down the plane, to provide a pretext for carrying out their genocidal plans.
Some 800,000 people were slaughtered in just 100 days before Mr Kagame's forces ousted the Hutu government.
A German diplomat told AFP news agency that Ms Kabuye had been in Germany on private business and that Germany was "bound to arrest her" by a French-issued European arrest warrant.
Ms Kabuye has visited the country before but under German law could not be arrested as she was part of an official delegation.
Ms Museminali said Rwanda had been aware of warnings about the risk of arrest, but said her country believed Ms Kabuye was protected by diplomatic immunity.
"We did not think they had any right or any base to arrest her."
"Rose Kabuye is going to fight it out and we are very confident that she will emerge innocent," she said.
Ms Kabuye's lawyer said she would be transferred to France "as quickly as possible".
Ms Kabuye and the eight other senior RPF officials were indicted in France in 2006 following an investigation.
The charge led to an immediate break in diplomatic relations between Paris and Kigali that has continued ever since.
Ms Museminali said the African Union was taking up Ms Kabuye's arrest with the EU.
"We do not think that France has any right to pass any legal jurisdiction over Rwanda, a country especially that has been implicated in the 1994 genocide," she said.
President Kagame has long accused France of complicity in the genocide.