Nations... and the tragic events that followed have confirmed that we were right," he said.

US President Barack Obama, also in Turkey, said a new deal had been agreed with France to speed up intelligence-sharing.

His secretary of state, John Kerry, landed in Paris late on Monday to discuss the attacks and described IS as "psychopathic monsters".

- Rocket launcher -

During pre-dawn raids in the southeastern French city of Lyon, police found "an arsenal of weapons," including a rocket launcher and Kalashnikov assault rifle.

More than 100 people have been placed under house arrest, 23 arrested and 31 weapons seized, Interior Minister Bernard Cazeneuve said.

As authorities scrambled to find those responsible, the grieving French tried to return to the humdrum of daily life.

Metro trains were packed with commuters, pupils returned to schoolsand a social media campaign urged everyone to visit cafes and bars on Tuesday night.

In the face of "barbarism... culture is our biggest shield and our artists our best weapon," said Culture Minister Fleur Pellerin.

Prime Minister Manuel Valls steeled the nation for more bloodshed, telling RTL radio that more operations "are still being prepared, not only against France but other European countries too."

Late on Sunday, French planes bombed the IS stronghold in northern Syria and more raids were reported Monday.

- The Belgian connection -

The manhunt continued for 26-year-old Salah Abdeslam, one of three brothers linked to the attacks.

One brother blew himself up in the Bataclan concert venue and was identified from a severed finger, while the third was arrested in Belgium but released without charge.

The brothers lived in