Belgian prosecutors said Monday police in the capital city have arrested 16 terror suspects in 22 raids, but top Paris massacre suspect Salah Abdeslam still remains at large.
Prosecutors said at least one suspect was wounded during the raids. Nineteen of the raids were in locations in and around Brussels.
"We fear an attack similar to the one in Paris," Prime Minister Charles Michel said Sunday.
Abdeslam is thought to have crossed into Belgium November 14, just hours after Islamic State gunmen killed 130 people and wounded hundreds of others in coordinated attacks in Paris. The suspected architect of the attacks, Abdelhamid Abaaoud, was killed Wednesday in a police raid in a northern Paris suburb.
Paris Assailants, Suspects
Status: Still at large
Name: Salah Abdeslam
Background: French national born in Belgium
Investigation: Considered eighth attacker; believed to be driver of car outside the Bataclan
Brussels' subway system and its schools are closed Monday as wary residents face a third day of lockdown and another work week overshadowed by the massive manhunt.
In Paris late Sunday, heavily armed security forces patrolled largely empty streets, as the city struggles to come to grips with the killings.
Earlier in the day, Belgian media outlets said police had arrested four people late Saturday, one possibly wearing a suicide belt. But Geert Schoorens of the federal prosecutor’s office said later he could “neither deny nor confirm” the reports. Authorities addressing reporters early Monday did not reference those reports.
US: No credible information on more IS threats
Separately, the U.S. State Department says it had "no information to confirm" reports that Islamic State extremists planned to launch more attacks in France, the United States and elsewhere.
A U.S. statement came in response to a question from the online activist group Anonymous, which said it had uncovered information about imminent plots that also included sites in Italy and Lebanon. The group said it forwarded relevant information to U.S. and British intelligence agencies.
The State Department also declined comment on whether it is taking extra security precautions at its facilities around the world, but said it is "already operating at a high level of security based on recent events."
WATCH: Related video report by Zlatica Hoke
In other developments Saturday, Russia said its security forces killed 11 Islamic State militants and destroyed an arms cache in the North Caucus region.
In Turkey, authorities announced the arrest of a Belgian citizen and two Syrians suspected of "aiding and abetting" IS terrorists. The Dogan news agency said the Belgian citizen is accused of carrying out reconnaissance for the Paris plot.
Lou Lorscheider contributed to this report from Washington.