Police react to a suspicious vehicle near La Carillon restaurant following a series of deadly attacks in Paris, November 15, 2015. REUTERS/Pascal Rossignol PARIS — French police officers raided homes of suspected Islamist militants across the country overnight in the aftermath of the Paris shootings, French Prime Minister Manuel Valls said on Monday as he warned of potential further attacks.

Valls said that since this summer, French intelligence services had prevented five attacks.

"We know that more attacks are being prepared, not just against France but also against other European countries," Valls said on RTL radio.

Police sources told Reuters that authorities conducted at least 110 house searches in cities around France overnight. One of these searches, in the Paris suburb of Bobigny, was part of the judicial investigation into the attacks at a football stadium, bars, and a concert hall where at least 129 people died.

French police made 23 arrests and seized assault rifles and drugs in a nationwide overnight sweep on suspected Islamist militants following Friday's attacks, the government said.

Interior Minister Bernard Cazeneuve said 168 homes were raided in France's major cities and elsewhere, and 104 people had been put under house arrest in the last 48 hours.

Police seized 31 firearms as well as computer hard drives and telephones, and illegal drugs were found in 18 of the raids, Cazeneuve told journalists.

One Islamist militant suspected of arms and drugs dealing was found to have Kalashnikov assault rifles, automatic handguns and bullet proof vests.

In one raid on the house of the parents of a suspect, police found military fatigues and a rocket launcher in addition to more bullet proof vests and automatic handguns.

According to the French TV news channel BFMTV, Valls announced that more than 150 searches had taken place since the state of emergency was announced on Friday.

Findings Sunday night included the arrest of five men in Lyon and the discovery of numerous weapons, including a rocket launcher.

The death toll was put 132 on Sunday, but reports on Monday said the increase may have been a counting error.

French media said the police also raided houses in Toulouse, Grenoble, and Bobigny.

"We are making use of the legal framework of the state of emergency to question people who are part of the radical jihadist movement ... and all those who advocate hate of the republic," Valls said.

On Friday, three coordinated teams of gunmen and suicide bombers carried out the wave of attacks across Paris in what President Francois Hollande called an "act of war" by Islamic State.

(Reporting by Geert De Clercq, Nicolas Bertin et Myriam Rivet,; and Sophie Louet; editing by Andrew Callus)