Belgian security officials meet Sunday to decide whether to extend a lockdown in Brussels over fears jihadists are plotting a Paris-style attack, as police stepped up their hunt for key suspects behind the carnage in the French capital.

The Belgian capital closed its metro system and shuttered shops and public buildings on Saturday as its terror threat was raised to its highest level over reports of an "imminent threat" of a major gun and bomb attack.

The city's historic Grand Place, usually bustling with tourists, was quiet, with just some stragglers crossing the cobblestones as an armoured vehicle stood outside the imposing town hall.

The national security committee will decide whether to extend lockdown, as security services intensified raids in the immigrant districts of the capital to track down jihadists thought to be behind the bloodshed in Paris.

Investigators are working around the clock to find Belgian-born Salah Abdeslam, one of the gunmen still on the loose after a coordinated wave of attacks on Parisian nightspots on November 13 that left 130 people dead.

Belgian Prime Minister Charles Michel said authorities feared a "Paris-style" assault "with explosives and weapons at several locations".

The carnage in Paris has put the EU on edge over fears that Islamic State-inspired extremists, who have killed hundreds around the world in recent weeks, can move freely through the bloc's passport-free Schengen zone.

In Madrid, fans for Saturday's El Clasico football match between Real Madrid and Barcelona were met by sniffer dogs, mounted police and countless identity checks.

In Turkey, police arrested a Belgian of Moroccan origin in connection with the Paris attacks in the resort of Antalya, the site of this week's G20 summit, along with two other suspects, probably Syrians.

Ahmet Dahmani, 26, is accused of helping to scout the Paris attacks and then preparing to illegally cross the Turkish-Syrian border to rejoin IS after arriving in Turkey from Amsterdam on his Belgian passport.

- 'All necessary measures' -

The UN Security Council on Friday authorised nations to "take all necessary measures" to fight Islamic State (IS) jihadists after a the wave of attacks across the world.

The resolution came after gunmen with an Al-Qaeda branch run by a notorious one-eyed Algerian militant besieged a luxury hotel in the Malian capital Bamako, killing 19 people, most of them foreigners.

Mali was struck a week after Paris and Beirut -- where 44 people were killed in IS bombings -- and three weeks after the militants claimed to have downed a Russian plane in Egypt killing all 224 on board.

In Cameroon, five people were killed and 10 wounded on Saturday when four teenage girls blew themselves up in a flashpoint northern town close to the Nigerian border that is often targeted by IS-allied Boko Haram Islamists.

France has been shaken to its core by the Paris attacks and a subsequent shootout on Wednesday between police and jihadists holed up in a Paris apartment.

Suspected attack ringleader Abdelhamid Abaaoud was killed in the raid along with his cousin Hasna Aitboulahcen and an unidentified suicide bomber, who, according to DNA tests, is not known to police.

- Seven released -

French police on Saturday released seven people arrested in the raid, but kept hold of Jawad Bendaoud, who has admitted lending the apartment to two people from Belgium "as a favour".

Abaaoud was a notorious Belgian jihadist thought to be fighting in Syria, and his presence in Europe raised troubling questions about a breakdown in intelligence and border security.

The European Union agreed Friday to rush through reforms to the passport-free Schengen zone by the end of the year as France extended a ban on public gatherings until November 30 and the start of a UN climate summit.

Seven attackers died during their assault on Paris including Brahim Abdeslam, who blew himself up outside a bar, and a huge manhunt is under way for his brother Salah Abdeslam, who is believed to have fled to Belgium.

He may be equipped with a suicide belt, according to Hamza Attou, one of two suspects charged by Belgian authorities for allegedly helping the 26-year-old return to the country after the attacks.

Attou's lawyer Carine Couquelet told French TV her client has described Abdeslam as very nervous on the journey.

"There are many possible theories: was (Salah) a logistical support, was he supposed to blow himself up? Was he not able to do it? We don't know."
Source: AFP