French investigators have searched the Paris home of conservative presidential candidate Francois Fillon, APA reports quoting BBC.
The Thursday morning raid was part of an investigation into an allegedly fake job given to his wife, Le Parisien newspaper reported, citing unidentified sources.
The authorities have not commented.
Mr Fillon denies any wrongdoing and has vowed to keep his candidacy going despite growing pressure.
He complained on Wednesday he was the victim of a "political assassination". But several allies have resigned from his campaign.
The allegations circling around the Fillon family focus mainly on his Welsh-born wife Penelope, who is also reported to be facing an investigation.
The Le Canard Enchaine newspaper alleges she was paid €831,400 (£710,000; $900,000) over several years for working as a parliamentary assistant for Mr Fillon and his successor, but had no parliamentary pass - raising questions over whether she did the work she was paid for.