In a joint operation on Friday involving German and Ukrainian authorities, police arrested four suspected members of an international band of art thieves as they attempted to sell the stolen painting in Berlin.

Police in Ukraine also arrested 20 further suspects thought involved with the gang.

Experts in Germany have authenticated the masterpiece – “The Taking of Christ,” painted around 1602 – as the work stolen from a museum in the southern Ukrainian city of Odessa in July 2008.

“The Ukrainian authorities have valued the painting in the tens of millions,” the German police statement said.

Some experts cited by Interfax news agency said the painting could fetch up to $100 million on the black market.

The source of the work, often also known as the “Judas Kiss,” has been in doubt in the past.

It was at one time thought to be a copy of a painting on display at the National Gallery in Dublin. But in 1950, a Moscow art expert declared that the painting in Odessa was in fact the work of Caravaggio.

The painting had been bought by a Russian ambassador to France and then given to Prince Vladimir Alexandrovich at the end of the 19th century.

After the Russian Revolution, the painting was given to an art school in Odessa and then the museum.