French authorities have found guns and bomb-making materials after the arrest of two men suspected of plotting an "imminent" attack five days before the first round of the presidential election, Interior Minister Matthias Fekl said on Monday.

"A few days ahead of a major election for our country, I wish to recall that everything has been put in place to ensure the security of this important date for our democracy and our republic," Fekl said.

The items were discovered during searches in the southern city of Marseille after the suspects - French citizens aged 23 and 29 - were taken into custody, sources told the French news agency AFP.

Photos of the two suspects were sent to the security staff of far-right candidate Marine Le Pen and centrist Emmanuel Macron last Thursday, AFP reported.

"The photos were passed to my security service from Thursday," Le Pen told AFP. An aide to Macron also confirmed his campaign team received the pictures, while conservative candidate Francois Fillon was warned about the danger on Friday, an aide said.

President Francois Hollande praised the work of the security forces, saying they had "done a remarkable job enabling us to arrest two people who will be brought before judges and police so that we can find out exactly what they were planning."

jbh/msh (AFP, dpa)