A Europe-wide manhunt for the perpetrators of a massive diamond heist in Belgium has resulted in 17 people being detained.

In what was described as one of the most brazen heists in criminal history, heavily armed men dressed as police officers stole 120 parcels of diamonds from the runway of Brussels airport in February.

The masked men made off with around $50 million worth of uncut gems in a raid on a Swiss plane which was being readied for take-off bound for Zurich.

Overnight police in Belgium, France and Switzerland mounted coordinated raids in which 31 people were initially detained.

Initially 24 people were rounded up in the Belgian raids, all aged between 30 and 35 years old, but a Brussels judge decided to keep 10 of them in custody. One suspect was held in France, and the rest in Switzerland.

More than 300 police were involved in the Belgian raids.

The suspect detained in France was believed to be a member of the gang of eight who carried out the heist.

"It's the only person that we can say at this stage that could have participated in the events on the tarmac," said Jean-Marc Meilleur, the Belgian prosecutor's spokesman.

"As for the others, we still need to investigate to find out whether they are intermediaries or if they are people who participated directly."

Belgian authorities have asked for the French suspect to be extradited.

Police in Geneva said they had questioned eight people after raids there and had subsequently released six of them, leaving two under investigation. Those figures differed slightly from the details provided by Belgian authorities.

Among those seized in Geneva were a businessman and a lawyer, while around 100,000 Swiss francs ($105,00) in cash and a number of diamonds were recovered, the police there said.

In Belgium, the raids recovered cash and luxury cars, the prosecutor's spokesman said.

Reuters/ABC