The charges against a French physicist detained last week on suspicion of links to Al Qaeda are "completely false," his brother said according to a report Tuesday.

Halim Hicheur was quoted in a news report posted on science journal Nature's Web site as denying that his brother — whom he identified as Adlene Hicheur — corresponded with members of Al Qaeda's North African offshoot, as French judicial officials allege.

The 32-year-old Frenchman of Algerian origin, who worked at the world's largest atom smasher in Switzerland, was arrested Thursday in France and preliminary charges have been filed against him.

Halim Hicheur said the family corresponded with people in Algeria where most of its relatives live, but said there was nothing "that would have made us think about violence."

He said the whole case might stem from Adlene Hicheur's recent withdrawal of euro13,000 (US$19,200) in cash he planned to use to buy land in Algeria.