A bomb has exploded at the Brussels Institute of Criminology in the north of city.
A car rammed through the barriers at about 3am and one or more attackers exploded a bomb near the laboratories which caught fire, RTL said.
The blast hit the empty building on Monday morning and no one was wounded - it is not clear what happened to the bombers.
State broadcaster RTBF said a car with two people on board accessed the site before scaling a ladded and launching a bomb at the building.
They are then said to have torched their vehicle
Belgium remains on high terror alert following by ISIS attack on Brussels airport and the city’s metro in March in which 32 people were killed by three suicide bombers.
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