A fourth person has been arrested in connection with the ongoing investigation into last Saturday’s explosion in The Hague which left six people dead and orphaned an eight-year-old boy.

The man was picked up on Wednesday evening and police have not released any more details about him, other than to say his relationship to the other three suspects is unclear. They were arrested earlier this week.

The police said on Wednesday they suspected the explosion was aimed at the bridal shop on the ground floor of the complex, which was completely destroyed in the blast and subsequent fire.

Meanwhile, more details have merged about the victims of the blast. Victim support group Namens de Familie said the 31-year-old man from Voorburg was visiting his girlfriend who lived in the block. She is in hospital but out of danger.

The 63-year-old man who died was married and his wife is in hospital but also now out of danger, the support group said.

The 44-year-old man who died lived alone and worked in The Hague. His wife and three young children live in Greece.

The other three fatalities are all members of the same family, and leave their son and brother, who is eight, alone.