The Dutch safety board is launching a preliminary investigation into the Arnhem fire which killed a man and his four-year-old son after they became trapped in a smoke-filled lift.

A woman and her eight-year-old daughter remain in hospital in a serious condition after the lift became stuck during a fire in the apartment block lobby. The family had been visiting grandparents on the fifth floor of the complex.

Board officials hope to conclude their preliminary investigation in a couple of weeks and will then decide if a formal probe should follow.

According to media reports, the 12-storey complex only had one entrance and this was blocked by the fire, which broke out around 1am. Emergency stairs on the edge of the building allowed people to go up or down but not to leave.

Eric Angenet, director of housing corporation Vivare, which owned the complex, told broadcaster NOS that the safety precautions had been approved by the fire brigade and that it does meet the proper standards. ‘But we will have to look again and see if that is still the case in this neighbourhood,’ he said.

The fire is thought to have been caused by fireworks and two boys, aged 12 and 13 are being questioned by police. They were held in police cells overnight and officials will decide later on Thursday if they should be released. According to NOS, they live in the block of flats hit by the fire.

The boys were reportedly caught on surveillance cameras setting off fireworks in the entrance to the property before the fire started.

The Hague

Meanwhile, police are also investigating if a fire which broke out in the car park of an apartment complex in The Hague was caused by arson.

Several people were seriously injured in the fire on Wednesday evening and dozens of people had to be evacuated. At least six cars and seven mopeds were destroyed in the blaze.