Four more people arrested as police hunt £77m Louvre jewel raiders

The two men and two women arrested on Tuesday morning are from the Paris region and range in age from 31 to 40, said the prosecutor, Laure Beccuau, whose office is heading the investigation.

Her statement did not say what role they are suspected of having played in the October 19 theft.

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French media report that one of those arrested, a 39-year-old already known to police, is believed to be the fourth member of the team thought to have carried out the daring daylight robbery and is from Aubervilliers, a suburb north of Paris that other suspects have connections to.

The other three alleged members of the so-called "commando" team have been previously arrested and face preliminary charges of theft by an organised gang and criminal conspiracy.

Their DNA has been found on the scene or on items linked to the robbery.

A woman arrested in October is accused of complicity.

The haul, valued at around £77 million, has not been recovered.

It includes a diamond and emerald necklace Napoleon gave to Empress Marie-Louise, jewels tied to 19th-century Queens Marie-Amelie and Hortense, and Empress Eugenie's pearl and diamond tiara.

Investigating magistrates have filed preliminary charges against three men and one woman arrested in October.

The robbery has focused attention on security at the Louvre, the world's most-visited museum.

The thieves took less than eight minutes to force their way through a window into the ornate Apollo Gallery, break into the jewellery display cases with disc cutters and make off with the trove, descending on a freight lift to meet up with riders on scooters who whisked them away.

The emerald-set imperial crown of Napoleon III's wife, Empress Eugenie, containing more than 1,300 diamonds, was later found outside the museum.