PARIS (REUTERS) - The Paris prosecutor said on Friday (Jan 13) that it had placed six more people suspected of involvement in last year's armed robbery of US reality TV star Kim Kardashian under formal investigation.

The latest development means 10 people in total - nine men and one woman - are under formal investigation over the robbery. The prosecutor will then decide whether or not to charge the group, two of whom are in their seventies, and one who could face a charge of illegally acquiring a machine gun.

In the early hours of Oct 3, thieves wearing balaclavas and fake police jackets burst into the luxury property in central Paris where Kardashian, who is married to US rap star Kanye West, was sleeping.

They tied her up at gunpoint before making off on bicycles with her engagement ring and other jewels worth 9 million euros (S$13.7 million), authorities said at the time.