The three were arrested in the Brussels area Tuesday and released by the investigating judge without charges a day later, the Belgian federal prosecutor said
The November shootings and bombings in Paris killed at least 130 people
. The investigation soon led authorities to Belgium, which has also suffered a spate of terror attacks.
The terror-related links between Paris and Brussels are uncanny. Investigators say that the same ISIS network was behind the Paris attacks in November and the suicide bombings in the Belgian capital last month.
Paris terror suspect Salah Abdeslam was captured
March 18 in the Brussels suburb of Molenbeek.
Terror analysts have speculated whether Abdeslam's arrest prompted the terror attacks in Brussels four days later
. At least 32 people died in the bombings at the Brussels Airport and at a subway station.
A night of horror in Paris
Assailants launched eight terror attacks in less than one hour
across Paris the night of November 13.
Three explosions took place at or outside the national soccer stadium, where France was playing Germany in front of a packed crowd. After the blasts, authorities found the bodies of a passer-by and three suicide bombers.
At around the same time, gunmen opened fire on a bar and restaurants across Paris. At least 39 people were killed.
And in the deadliest attack, three gunmen opened fire at a rock concert at the Bataclan theater and held audience members hostage. By the end of the siege, 89 people were dead, along with three assailants.
A morning of terror in Brussels
The terror attacks in Brussels targeted travelers during the morning rush hour March 22.
Two bombs exploded within a minute of each other
at the Brussels Airport, killing at least 10 people.
About one hour later, a suicide bomber detonated explosives on a Brussels subway. Authorities believe another person who appeared on surveillance video might be linked to the attack.
Why Brussels and Paris?
The Brussels terrorists actually planned to attack Paris instead of the Belgian capital
. But they changed their minds when investigators closed in, the Belgian prosecutor's office said.
So what makes Paris an alluring terror target? France is part of a U.S.-led coalition that has been bombing ISIS targets.
Midway through the killings at the Bataclan, the gunmen stopped and asked each other, "Where is the singer? Where are those Yanks? It's an American group, you're bombing us with the Americans, so we're going to hit the Americans and you," according to a witness cited in police documents
The gunmen then told victims they had been dispatched from Syria by ISIS to carry out the attack to avenge French airstrikes in Iraq and Syria.
But Belgium is also a valuable terror target. Many Muslim youth there feel marginalized
. Per capita, more young Belgian men are traveling to join ISIS
in Iraq and Syria than any other European country. And authorities worry about what they could do if they return.