Manuel Valls said the weekend roundup of suspected Islamist radicals was the beginning of efforts to deal with homegrown anti-Semitic terrorism, Radio France Internationale reported.
"We know there are dozens, even hundreds of individuals who are capable of organizing themselves like the group that has just been dismantled," Valls told a radio interviewer Monday.
He said indoctrination in prison and the distribution of radical Islamist propaganda on the Internet and satellite television have contributed to what he labeled "internal terrorism."
None of those arrested last weekend had links to France's former colonies in North Africa. All were born and raised in France and converted to Islam.
Valls said dismantling groups operating in France won't be easy.
"They are very mobile individuals who feel they are under surveillance and who make little use of mobile phones," he said.