A 16-year-old has been arrested in his home in Paris for allegedly planning to carry out an attack.

A security official said Sunday that the boy was arrested a day earlier after France's intelligence services "detected a threat."

The official said the arrest isn't linked to the arrests last week of four women and a man over aborted attacks.

The boy had already been under house arrest due to France's state of emergency in which dozens of people are under special watch, said the official who was not authorized to speak publicly about the arrest and asked not to be named.

French Prime Minister Manuel Valls reiterated in an interview on Sunday that France is under maximum terror threat and "every day attacks are foiled ... (including) as we speak."