Thue FBI warned Dutch police about two of the Brussels attackers one week before they blew themselves up, Reuters reported. The Islamic State attacks killed 35 people on March 22.
Ibrahim and Khalid El Bakraoui were two brothers who took part in the attacks. Ibrahim had been deported to the Netherlands from Turkey in July 2015for attempting to reach Syria and join the Islamic State, according to Turkey.
He was not detained or deported to Belgium on his arrival.
The FBI shared the information with Dutch police about the Bakraoui brothers on March 16. This information was passed on in a meeting between Dutch and Belgian authorities the next day, the Dutch interior minister said.
In the wake of attacks a string of failures by security services have come to light, including poor communication between security agencies in different European countries.
The Islamic State jihadists had also collected information about the home of Belgian Prime Minister Charles Michel. Building plans and photos were found on a computer dumped in a rubbish bin, according to the BBC.
There were street celebrations in several parts of Belgium after the Brussels attacks, vice Prime Minister of Belgium Jan Jambon has admitted.
Four days before the attack, during a police raid which culminated in the arrest of Paris attacker Saleh Abdeslam, youth in the radicalized district of Molenbeek threw projectiles at police. Yet the incident was not covered on Belgian news outlets.