A total of 23 people have been arrested and dozens of weapons seized in a series of raids on suspected Islamist militants across France, officials say.

The crackdown follows multiple attacks on bars, restaurants, a concert hall and a stadium in Paris on Friday, in which 129 people were killed.

A police operation is also under way in Brussels, Belgium, with reports that one suspect was arrested.

Shots and explosions have been heard in the district of Molenbeek.

France held a nationwide minute of silence at midday local time (11:00 GMT) for the victims.

French PM Manuel Valls said the attacks were organised from Syria.

He added that the authorities believed new terror attacks were being planned in France and other European countries.

Meanwhile two more Paris attackers were named, along with five already identified. One is confirmed to have entered Greece as a migrant earlier this year.

Police have named Brussels-born Salah Abdeslam, 26, as a key suspect, and a manhunt is under way. He was reportedly stopped by officers in the wake of the attacks but then let go.

Meanwhile, French aircraft have attacked Raqqa, the stronghold in Syria of the Islamic State group, which has said it carried out the attacks.

Valls said that France was dealing with a "terrorist army", rather than a single terrorist group.

"We know that operations were being prepared and are still being prepared, not only against France but other European countries too," he said.

(BBC)