Francois Fillon (L), former French prime minister, member of The Republicans political party and 2017 presidential candidate of the French centre-right, and his wife Penelope Fillon stand close at the end of a political rally in Paris, France, January 29, 2017. REUTERS/Pascal Rossignol

PARIS (Reuters) - French presidential frontunner Francois Fillon and his wife Penelope were being questioned by investigators on Monday following press allegations that she was paid for fake jobs, a source close to the probe told Reuters.

Francois Fillon had said after the probe was opened last week that he wanted to be heard by the investigators. Such questioning is a normal step in a preliminary probe and not a sign of culpability.

The source confirmed an earlier report by BFM TV.