Police search the boot of a car in Brussels today. Associated Press Associated Press

Updated at 1pm

HEAVILY ARMED POLICE and soldiers are patrolling key junctions, and subways have been closed in Belgium’s capital as the government warns of a threat of Paris-style attacks.

At least one suspect from the deadly Paris attacks is at large, and was last seen crossing into Belgium.

Prime Minister Charles Michel said the decision to raise the threat alert to the highest level was taken “based on quite precise information about the risk of an attack like the one that happened in Paris … where several individuals with arms and explosives launch actions, perhaps even in several places at the same time”.

The Belgian Federal Prosecutor’s office said that several weapons were discovered during the search of the home of one of three people arrested in connection with the Paris attacks, but said no explosives were found.

And in Turkey, officials detained 26-year-old Ahmad Dahmani, a Belgian national of Moroccan origin, who was believed to have been in contact with the Paris attackers.

Investigation

Authorities across Europe, the Middle East and in the US are trying to determine how a network of primarily French and Belgian attackers with links to Islamic extremists in Syria plotted and carried out the deadliest violence in France in decades — and how many may still be on the run.

Belgium’s national crisis centre raised its terrorism alert for the Brussels region to Level 4, which indicates a “serious and immediate threat”.

Belgium’s special security cabinet also held an emergency meeting this morning.

Belgian Army soldiers patrol a street in the center of Brussels on Friday AP / Press Association Images AP / Press Association Images / Press Association Images

In Brussels, residents were recommended to avoid gatherings, train stations, airports and commercial districts.

Service was halted on the Brussels Metro, as well as on streetcar lines that run underground.

The prime minister, speaking at a news conference after the emergency government meeting, said:

“We urge the public not to give in to panic, to stay calm. We have taken the measures that are necessary.”

He said that the government’s crisis cabinet would meet again tomorrow afternoon to reassess the threat.

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