A woman with French and Swiss nationality was kidnapped Saturday in Gao, the biggest city in Mali's restive north, officials said.

"We immediately launched a search," a security source said on condition of anonymity, without revealing her identity or how she was abducted.

Two elected officials in Gao, more than 1,200 kilometres (750 miles) from the capital Bamako, confirmed the kidnapping.

There have been no claims of responsibility.

A French diplomatic source in Paris said they were trying to verify the information.

Northern Mali fell to terrorist groups linked to al-Qaida from March 2012. These forces were driven out of key towns when France led an international military intervention the following year.

But barely a week goes by without attacks on security forces despite a peace pact signed in May and June last year following lengthy negotiations between the government, groups backing it and Tuareg rebels. Kidnappings are rare.