The wife and brother-in-law of the missing Earl of Shaftesbury, Anthony Ashley-Cooper, have been arrested by police on suspicion of his murder, according to French press reports.
Djamilia M'Barek, 37, was detained in Cannes on Friday, while Mohammed M'Barek, 40, was arrested on Saturday in Munich and is to be brought back to France.
Lord Shaftesbury, 66, was last seen in the seaside resort on 6 November. Police said in December that they were treating the disappearance of the thrice-married aristocrat as murder.
The Earl was estranged from Djamilia M'Barekat - an Algerian-Dutch nightclub hostess he married in 2002 - at the time of his disappearance. Lord Shaftesbury had arrived in the Riviera on 3 November after telling his son and heir, Lord Ashley, 27, that he wanted to "sort things out" with her.
The night before his disappearance, he visited a basement hostess bar in Cannes, a regular habit. The next day he left the £130-a-night Noga Hilton and has not been seen since.
Two Sussex police detectives flew to France in December to help with the search for the missing earl. A Sussex police spokesman said yesterday they had no information about the arrest of his relatives.