Two people were killed on Monday in an explosion in the Belgian city of Antwerp that destroyed three adjacent houses.
Fourteen people were wounded in the incident that has been ruled out as a terrorist attack.
Five of the victims are seriously injured, while another was in critical condition.
Two bodies were recovered from under the debris on Tuesday.
At least one building totally collapsed. Rescue workers were still going through the debris early Tuesday, although they had no indication that there were more victims.
Police said an investigation was underway into the cause of the blast.
Belgian media said it was likely to have been a gas explosion.
Belgium has been on high alert since deadly suicide bombings in 2016 and a wave of extremist attacks across Europe.