An anti-terror operation was under way at a shopping centre in central Brussels on Tuesday, Belgian prosecutors told the Belga News agency, adding that one suspect had been arrested.
Prime Minister Charles Michel was holding an emergency meeting with members of his security cabinet, Belgian media reported.
The incident began at about 6:30am (0430 GMT) Tuesday after a report of a man acting suspiciously near the City 2 shopping centre triggered a bomb alert, broadcaster RTL reported.
A bomb squad team was deployed at the shopping centre, one of the main retail hubs of the Belgian capital.
Only one single exit remained open at the nearby Rogier metro station, where soldiers checked passengers bags and belongings.
Pictures showed police sealing off the immediate area.
Belgium is still reeling from the Islamic State suicide bombings at Brussels airport and on the city's metro on March 22 which killed 32 people and wounded hundreds more.
And the incident comes only days after Belgian authorities charged three men with "attempted terrorist murder" after raiding dozens of homes linked to a reported threat to fans during a Euro 2016 football game.
Prosecutors charged the three men, named as Samir C., Moustapha B. et Jawad B., but released nine others after questioning.
The areas searched included neighbourhoods in Brussels where November's jihadist attacks in Paris and the Brussels suicide bombings had planned their assaults.
Authorities said at the time they were responding to a need for "an immediate intervention".
Per capita, Belgium has produced the highest number of so-called foreign fighters in the EU who have travelled to wage jihad in Syria and Iraq, an estimated 500.
After Saturday's swoop, Michel said the country would be taking "additional and updated security measures."
However, he pledged that public events planned for the coming days would go ahead, he said, including those linked to the Euro championships.
"We want to continue living normally," the premier said.
And despite the lockdown in the area, the terror alert level in Brussels remained at level three, Belga reported.
On Saturday, a source close to Belgian authorities confirmed to AFP that several leading political figures have recently had their security increased.
According to state broadcaster RTBF and daily Flemish newspaper Het Nieuwsblad, 30 people and their families have had their personal security stepped up since Friday, including the prime minister, interior minister and justice minister.
Euro 2016 host France is also on high alert for possible attacks during the championship.
AFP
Tue Jun 21 2016
Police cars block the area as police officers gather at the scene of a bomb alert at the City2 shopping mall in the Rue Neuve in the city center of Brussels on June 21, 2016. - AFP PHOTO
Who is Prabowo Subianto, incoming president of Indonesia?
A wealthy ex-general with ties to Indonesia's popular outgoing president and its dictatorial past, looks set to be its next leader.
Iran's supreme leader says Hamas leader's death will not halt 'Axis of Resistance'
The "Axis of Resistance", built up with years of Iranian support, includes Hamas, the Lebanese Hezbollah group, the Houthi movement in Yemen, and various Shi'ite groups in Iraq and Syria.
Putin says Russia willing to seek compromises between Iran and Israel
Russia is ready to help seek compromises between arch-foes Israel and Iran, President Vladimir Putin said on Friday, saying these would be difficult but possible.
What proposals will Russia push at the BRICS summit?
The proposal is also to establish a BRICS reinsurance company to allow uninterrupted shipment of goods and key commodities between members.
Indonesia's free meals plan in the spotlight as Prabowo readies for office
Prabowo calls the programme one of the main drivers of economic growth, eventually set to add an estimated 2.5 million jobs.
Astro AWANI's revamped English news website, AWANI International, launches on Oct 21
Astro AWANI's revamped English platform delivers in-depth global news and expert analysis to keep you informed on key developments.
Israeli strikes kill 33 people in Jabalia refugee camp in Gaza, medics say
Residents of Jabalia said Israeli tanks had reached the heart of the camp after pushing through suburbs and residential districts.
Liam Payne's ex-partner calls for media restraint after 'painful' death
Cheryl Tweedy used her statement to urge the media to remember they had a seven-year-old son, Bear, who could read the reports.
Analysts: Indonesia's strong MoF leadership team to boost investor confidence
Sri Mulyani Indrawati as head of Indonesia's Ministry of Finance is expected to instil confidence among investors.
Biden offers both a carrot and a stick to Israel as his term nears an end
Israel has frequently resisted US advice and has caused political difficulties for the Biden administration.
Putin says BRICS will generate most of global economic growth
Russian President Vladimir Putin will host a summit of the group in the city of Kazan on Oct. 22-24.
ISIS Malaysia's perspective of Budget 2025
An excellent rakyat-centric budget under the overarching principle of a caring and humane economy.
Budget 2025: Record increase in STR, SARA aid initiatives
The government will provide a significant boost to the Sumbangan Tunai Rahmah (STR) and Sumbangan Asas Rahmah (SARA) initiatives next year.
Budget 2025: EPF contributions to be made mandatory for foreign workers – PM Anwar
The government plans to make it compulsory for all non-citizen workers to contribute to the Employees Provident Fund (EPF).
What policies to expect from Indonesia's new President Prabowo
Prabowo will be open to foreign investment, his aide has said, such as by offering investors management of airports and sea ports.
Budget 2025: Govt allocates RM470 mil to empower women's participation in PMKS
The Women's Leadership Apprenticeship Program will be intensified as an effort to produce more female corporate personalities.
Israel sends more troops into north Gaza, deepens raid
Residents of Jabalia in northern Gaza said Israeli tanks had reached the heart of the camp, using heavy air and ground fire.
Indonesia ramps up security ahead of Prabowo's inauguration
Prabowo Subianto will be sworn in as Indonesia's president on Sunday with Vice President-elect, Gibran Rakabuming Raka, also taking office.
Immediate allocation of RM150 mil for local authorities, DID to tackle flash floods
Datuk Seri Anwar Ibrahim said this allocation is intended to address the recent flash floods that hit the capital and several major towns.
Budget 2025: Sabah, Sarawak to continue receiving among highest allocations - PM
Sabah and Sarawak continues to be prioritised under Budget 2025, with allocations of RM6.7 billion and RM5.9 billion respectively.