A bomb exploded at the Brussels Institute of Criminology in the north of Brussels on Monday but the building was empty and no one was wounded, broadcaster RTL said.
Reuters reported that a car rammed through the barriers at about 3 am local time and one or more attackers caused a bomb explosion near the laboratories which then caught fire.
Police have deployed in force and sealed off the area.
The institute assists and advises Belgium's justice authorities in carrying out their inquiries, reported The Associated Press.
Brussels has remained on high alert — at terror alert level three — since the infamous 22 March attacks in which 32 people were killed.
The attacks had taken place at Zaventem airport and Sint Jans Molenbeek Metro station. Both attacks were claimed by the Islamic State.
The airport bombings were carried out by Ibrahim El Bakraoui and Najim Laachraoui — who was the alleged bomb-maker for the 13 November attacks on Paris, AFP had reported.
The metro bomber was Khalid El Bakraoui, Ibrahim's brother.
On 10 August, a bomb scare at Zaventem airport had sent security forces in Brussels into a tizzy. State prosecutor Eric Van Der Sypt had said that his office had received information about possible bomb alerts and had opened an investigation.
However, two aircraft landed safely at the airport after the threat, although some other planes had been diverted to other airports.
With inputs from agencies