GENEVA/PARIS (Reuters) - Authorities in Switzerland and France have arrested 20 people they say are linked to a multi-million dollar Moroccan drug smuggling network and have frozen accounts at several banks in Geneva, they said on Wednesday.

The family network, thought to be run by Swiss and French citizens of Moroccan origin, sold cannabis from the North African country to France via Spain and laundered the money in Switzerland, they said.

As part of the operation, Swiss authorities raided a secret safe tucked behind a wardrobe containing cash and valuables worth around 3 million Swiss Francs ($3.20 million) as well as

In France, prosecutors said they had seized over a million euros in cash, two works of art with a combined value of one million euros ($1.29 million), two automatic handguns, and six gold ingots.

Investigators said the proceeds of the network were channeled through a complex system of Swiss bank accounts and fake companies and reported that around 12 million euros ($15.48 million) were handled between May and October.

"The mechanism allowed for the link between drug trafficking in France and the recycling of earnings in Switzerland to be camouflaged," the Swiss Attorney General's office said in a statement.

Swiss police are also questioning staff at a "long-standing Geneva company" as well as an employee of a large international bank based in the Swiss city suspected of assisting with the payments.

In accordance with Swiss privacy restrictions, it did not name the companies involved.

Switzerland is seeking to widen the powers of its anti-money laundering unit and last year identified suspicious asset flows totaling a record 3 billion Swiss francs. ($1 = 0.9387 Swiss francs) ($1 = 0.7751 euros)

(Reporting by Emma Farge; Additional reporting by Leigh Thomas in Paris; Editing by Andrew Osborn)