PARIS -- French police launched on Tuesday a raid operation at the home and offices of former president Nicolas Sarkozy as part of the investigation into suspected illegal financing of his 2007 election campaign by L'Oreal heiress Liliane Bettencourt.

Police raids were conducted while the former head of state left for Canada with his family on holidays, Sarkozy's lawyer Thierry Herzog was quoted by Le Monde daily as saying.

"These investigations ...as expected, are unnecessary procedures," Herzog said.

Losing immunity from prosecution last month, Sarkozy could be questioned for the allegation, although he has denied any wrongdoing, the daily said.

A former bookkeeper of Bettencourt unveiled in 2010 that 150,000 euros (189,146 U.S. dollars) were offered to finance Sarkozy's 2007 campaign.