A former spy in Germany who claimed to have foiled a Mafia assassination attempt against a former Pope has gone on trial accused of tax evasion.

Werner Mauss, dubbed the "German James Bond", is accused of stashing more than €15m (£13m, $17m) in offshore accounts.

Mauss, 76, denies the accusations, and his lawyers said the accounts were opened in the 1980s by Israeli and Western secret services to fund covert operations around the world.

According to a court in the city of Bochum, Mauss had a substantial income from foreign investments between October 2003 and March 2013, which he did not declare to tax authorities.

The former vacuum cleaner salesman claims that as a spy he helped thwart an attempt by the Mafia to poison former Pope Benedict XVI, freed hostages held by Colombian rebel group Farc, and was involved in operations against Islamic State.

The offshore accounts allegedly used by Mauss are located in Luxembourg, Liechtenstein and the Bahamas.

His lawyer claims that he is unable to mount a proper defence as he is bound by confidentiality agreements linked to his decades working as a spy.

If found guilty, Mauss could be jailed for up to 10 years.