Qatari emir's Riviera mansion targeted in gun point robbery
The emir, Sheikh Tamim bin Hamad Al-Thani, was not present when the four people broke into his residence in Mouans-Sartoux, the source said, confirming a report from RTL broadcaster.
"The people present complied under threat (with the burglars) when they saw the weapon," the source said.
But the source added that they "did not have a pistol put to their heads".
The burglars made off with "luxury items, particularly watches", the source said.
Though the emir was not present, members of his family were in the residence.
A number of law enforcement organisations in the cities of Grasse, Nice and Marseille have opened an investigation.
The family of Sheikh Hamad bin Khalifa Al Thani, who abdicated in 2013 on behalf of his son, has owned since the 1990s a mansion sprawling over 30 hectares (75 acres) in Mouans-Sartoux.
In 2016, he made a gift of one million euros to the small commune.