BRUSSELS — Belgian police arrested five more people in a new series of anti-terrorism raids yesterday, prosecutors said, as the capital Brussels was locked down for a third day under a state of maximum alert.

The arrests bring to 21 the total number of people detained since police launched a major security operation last Sunday night, with 16 people having been taken into custody earlier, they said.

“Following the operation of last night, five more house searches were conducted in the Brussels region and two more in the Liege region. Five persons were arrested during these searches,” the federal prosecutor’s office said in a statement.

“A total of 21 persons were arrested since yesterday. They are currently questioned by the police.” Around €26,000 (S$39,204) in cash was seized during one of the searches and other items seized by police are being examined, the statement said. Belgium-born Salah Abdeslam, one of two brothers believed to have been involved in the Nov 13 Paris attacks, has thus far eluded authorities.

Prime Minister Charles Michel said Brussels, a diplomatic and business hub home to the European Union (EU) and the North Atlantic Treaty Organization (NATO), faced a “serious and imminent” threat of attacks similar to those claimed by IS jihadists which left 130 people dead across Paris.

Belgian police fear Abdeslam has returned home to launch new attacks.

At the same time, Germany has kept security along its border with Belgium at a high level since the Paris attacks, a German police spokesman said after media reports that Abdeslam was spotted near the frontier.

Several Belgian media carried unsourced reports saying he had been seen in a car near the eastern city of Liege heading towards Germany. There have been numerous reported sightings in recent days. “Intensive border security measures have been in place since last week,” the German police spokesman told Reuters.

The metro, museums and schools, many shops and cinemas stayed shut yesterday in the usually bustling EU capital, as many staff worked from home. On the Grand Place, a historic central square that usually draws crowds of tourists and local people, an armoured military vehicle was parked under an illuminated Christmas tree.

NATO, which had raised its alert level since the Paris attacks of Nov 13, said its headquarters in the city were open, but some staff had been asked to work from home and external visits had been cancelled. EU institutions were also open, patrolled by soldiers.

Interior Minister Jan Jambon told RTL radio, however, that Belgium’s capital was still operating. “Apart from the closed metro and schools, life goes on in Brussels, the public sector is open for business today, many companies are open,” he said yesterday morning.

The city’s buses were running normally and many shops in the suburbs were open. Among those who decided to go out on Monday was Ms Zineb Toubarhi, a business engineering student in Brussels, who was waiting to catch a bus on a frosty morning. “I am going to my friends’ place to look after their children today. They must go to work and the schools are closed. I’ve had classes cancelled at the university so I will help them,” she said. “It feels strange to see armed soldiers in the streets, but this is for our security. So, I don’t know why, but I am not afraid.”

In France, British Prime Minister David Cameron yesterday offered French President Francois Hollande full support in the fight against IS — including the use of an airbase in Cyprus and air-to-air refuelling services for French aircraft.

French police also released a photo of the third of three men who blew themselves up outside France’s national stadium. The man in the picture passed through Greece with one of the other suicide bombers, carrying a Syrian passport in the name of Mohammad Mahmod, said a source close to the investigation.

Meanwhile, Eagles of Death Metal, the Californian band that was playing at the Bataclan, spoke for the first time since the attacks, with singer Jesse Hughes saying many fans died trying to protect their friends. “So many people put themselves in front of people,” he said, in an excerpt of an interview with media outlet Vice News. AGENCIES