The French have arrested nine terror suspects who were allegedly planning to blow up the Paris subway.

Terror suspects detained in France had been eyeing up the Parisian metro network, an airport and the headquarters of the domestic intelligence service as possible targets, sources close to the investigation said.

The suspicions were based on an intelligence tip-off from Algeria and from telephone surveillance, although there is no hard evidence they had settled on a particular target, they said.

Nine people were detained by police early Monday in a series of raids west of Paris in what officials said was a crackdown on suspected Islamic terrorist activities.

Surely the French must be asking themselves: "Why do they hate us?"