Belgium has raised the terror alert level in its capital Brussels to the highest possible. The interior ministry has called on local authorities to close the Brussels metro for the weekend, citing the "serious and imminent threat."

"Following our latest evaluation... the center has raised its terror alert to level 4, signifying a very serious threat, for the Brussels region," an official statement said, according to AFP.

"The analysis shows a serious and imminent threat requiring specific security measures as well as detailed recommendations to the population," the statement added.

The Coordinating Body for Threat Analysis (OCAM) of interior ministry issued a statement Saturday, calling for people to avoid crowded public places and not to attend big events like football matches or music concerts.

"The advice for the population is to avoid places where a lot of people gather together like shopping centers, concerts, events or public transport stations wherever possible," the statement said, according to DW.

Media reports said that two of the Paris suicide bombers had been living in the Belgium, according to Sputnik. More than half a dozen suspects were arrested in the country in connection with last week's terror attacks in the French capital, which killed at least 129 people and wounded 350 others.