The recovered painting - Conversation with the Gardener by Renoir

"We consider all of them as perpetrators of the crime," district public prosecutor Ylva Johansson said.

"It all hangs together, it is one and the same deed."

From the outset police believed a number of people were involved in the crime, as diversionary phone calls reporting car fires were made at the same time as the gallery alarm went off at police headquarters.

One of the suspects, a lawyer, was accused of delivering a demand for a 30 million kronor (�2m)

All ten have pleaded innocent.

Gunpoint

On 22 December last year, masked raiders snatched a self-portrait by the Dutch master, Rembrandt, and two works by the French impressionist Renoir.

The three thieves walked into the museum in central Stockholm as it was preparing to close for the day.

One, armed with a machine gun, held up security staff while the other two ran to different rooms upstairs

Rembrandt self portrait from 1630

After ordering guards there at gunpoint onto the ground, the two thieves went straight for their target paintings.

Within moments all three had left the building and sped off into the darkness on a small motor boat waiting for them near the museum.

Johannsson described the robbery as "very professionally planned and carried out."

The subsequent confusion apparently gave the robbers the time they needed to escape.

Only one of the paintings - Pierre-August Renoir's Conversation with the Gardener - has been recovered.

It was discovered in a bag during a drugs raid unrelated to the art theft.

Still missing are a Self Portrait (1630) by Rembrandt, and Renoir's Jeune Parisienne.