Police have arrested a man over art thefts in two Dutch towns several months apart last year.
The 58-year-old, arrested at his home in the central town of Baarn, is suspected of stealing works by Vincent van Gogh and Frans Hals from museums in the towns of Laren and Leerdam.
Neither of the paintings has been recovered.
Frans Hals's Two Laughing Boys with a Mug of Beer, is reputed to be worth some €15m (£13m; $17.5m).
Police said the search for the two works continued but the arrest was an important step in the investigation.
Van Gogh's Spring Garden, also known as Parsonage Garden at Nuenen in Spring, was stolen during a break-in at the Singer museum in Laren, a short distance from Baarn in March last year.
The painting had been on loan from a museum in the northern city of Groningen and the building was closed because of coronavirus measures at the time. The thief broke down two glass doors with a sledgehammer before making off with the canvas.
Dutch art detective Arthur Brand said later he had received two "proof of life" photos which he said showed that the Van Gogh canvas had not been destroyed.
Then in August the Frans Hals work was seized from a museum in Leerdam, south of Utrecht.
This work had been stolen twice before, in 1988 and 2011, but was later returned.
Mr Brand told the BBC at the time that such thefts were not uncommon as criminals had previously bought stolen works of art to exchange them for shorter jail terms. Dutch TV programme Crime Desk reported earlier this year that the Van Gogh had been bought by a suspect in a cocaine trafficking ring but negotiations to have it handed back had failed.
The suspect was arrested in an early morning raid in the centre of Baarn.
Mr Brand told Dutch newspaper Algemeen Dagblad that it was unlikely that the suspect knew the location of the paintings as stolen artwork was often moved around quickly by criminal gangs.
A spokeswoman for the Singer museum said she hoped the arrest would lead to the Van Gogh painting so people could once again enjoy it.