Two Belgian nationals arrested in connection with Tuesday’s armed robbery at the Tefaf fine arts fair in Maastricht have been released without charge, police said on Wednesday evening.

The two men were arrested shortly after a gang of four stole a quantity of jewelry from a display case at the fair. They were stopped in their gray car with Belgian plates on the A2 motorway after they were said to be acting suspiciously.

The men’s lawyer had earlier described their arrest as a misunderstanding and said nothing had been found in their car to connect them to the robbery.

The police have now renewed their hunt for four men, who wore flat caps and glasses as one of them smashed open the display case. Another brandished a gun at visitors to the fair.

Police have confirmed that the gang made off with a quantity of jewelry but have not said what. Several people have suggested that a necklace containing a very large yellow diamond was part of the haul.

They are also now appealing for everyone with dashcam footage in an effort to trace the robbers.

The Tefaf fine art fair closes on Thursday.