* Part of network smuggling cannabis to France, Spain
* Brothers admitted getting cash in plastic bags
* One ex HSBC employee, other worked for Geneva firm
By Emma Farge
GENEVA, Jan 29 (Reuters) - Two brothers who worked for financial firms were sentenced to prison on Tuesday for laundering money through Swiss bank accounts for a Moroccan drug smuggling ring, Geneva authorities said.
The two men were part of a family network thought to be run by Swiss and French citizens of Moroccan origin selling cannabis from North Africa to France and Spain, said the Geneva judicial authority.
Swiss and French authorities launched an investigation code-named 'Virus' in October after they discovered a safe hidden behind a wardrobe in Geneva holding cash and valuables worth around 3 million Swiss francs ($3.25 million).
Investigators arrested 20 people and froze accounts at several Geneva banks.
Switzerland is seeking to widen the powers of its anti-money laundering unit as part of a campaign to shed its image as a tax haven.
In 2011, it identified suspicious asset flows totalling a record 3 billion Swiss francs.
Geneva's judicial authority said the brothers, who were unnamed in accordance with Swiss privacy laws, had admitted accepting bundles of cash in plastic bags as part of the operation.
One of the brothers is a former employee of HSBC, the bank confirmed on Tuesday, and faces up to two years in prison.
"We fired the employee after our internal investigation last year. Our investigation showed that the bank was not in any way involved in this matter," said HSBC spokesman Medard Schoenmaeckers.
The man's older brother works for a "Geneva-based wealth management firm" and was sentenced to a maximum sentence of three years, the Geneva authority said.
A third person accused of being involved in the operation is still awaiting a verdict, it added.
($1 = 0.9221 Swiss francs) (Reporting by Emma Farge; Editing by Andrew Heavens)