Belgian counter-terror police have arrested a man suspected of plotting an attack against the US embassy in Brussels, federal prosecutors said Monday.
The police on Saturday arrested the man following "converging signs raising fears of an attack against the US embassy," the prosecutor's office said.
"The suspect has been detained for an alleged attempted attack within a terrorist context and preparation of a terrorist offense," it said in a statement.
The man identified only as M.G. appeared Monday morning before an investigating judge who ordered him held, it added.
The suspect denies any involvement in the alleged plot.
A source close to the investigation told AFP the suspect is a Belgian man around 40 years old and a convert to Islam who had "raised suspicion because of his behaviour".
He had been seen "scouting" the embassy area before he was arrested, the source added, speaking on condition of anonymity.
The source declined to say whether the suspect fit the profile of a jihadist.
A spokesman for the US embassy said, "We have no comment at this time."
Jihadists have staged a number of attacks in Brussels, which hosts the headquarters of the European Union and NATO.
The worst was on March 22, 2016, when suicide bombers killed 32 people and wounded hundreds of others at Brussels airport and a metro station near EU buildings.
The Islamic State group claimed responsibility for the twin attacks.
- Previous attacks in Belgium -
Since 2016, several other attacks, some of them also claimed by IS, have targeted Belgian police or soldiers.
The last "terrorist attack" occurred in the eastern city of Liege on May 29 last year when Benjamin Herman shot dead two women police officers and a student.
He shouted "Allahu Akbar" (God is Greatest) before being shot dead by the police.
Since the end of January 2018, the terror alert level in Belgium has been set at two, which means an attack is considered unlikely, the same as it was before January 2015.
A level three alert -- indicating an attack is possible and likely -- was set later in January 2015 after police smashed a jihadist cell in the eastern city of Verviers.
That Belgian police raid occurred a week after attacks against the Charlie Hebdo magazine and Jewish supermarket in Paris.
The level four alert -- which means a serious and imminent threat of attack -- has been put in place twice but for limited duration.
It was imposed for the first time for a week in the wake of the November 13, 2015, attacks in Paris which claimed the lives of 130 people and wounded hundreds of others.
It was then raised from three to four in the days after the March 2016 attacks.
Police say they believe the same cell was behind both the French and Belgium attacks.