Opposition parties in Amsterdam are pressing for an inquiry after it emerged that the gun that mayor Femke Halsema’s son was arrested with in July belonged to her husband.

Film producer Robert Oey admitted that the revolver was taken from a drawer of the mayor’s residence on Herengracht, where he lives with Femke Halsema. The couple’s 15-year-old son was stopped by police after for breaking into an unoccupied houseboat with an illegal weapon and emptying a fire extinguisher into a canal.

Halsema chastised the Telegraaf newspaper for dedicating three pages to what she called a private matter when it broke the story. On Monday she reasserted her view that her family life was not a subject of ‘public debate’, but the FvD and VVD groups on the council questioned why an illegal weapon was being kept at the mayor’s official home.

In her initial response to the incident Halsema described the gun as a replica, but in an interview published in NRC at the weekend, Oey said it was a genuine revolver that had been deactivated. He had owned it for several years and used it as a prop on movie sets.

‘More boxes’

He said he had put the gun in a drawer before leaving on a business trip to Thailand in July, a few days before his son was arrested. ‘I thought: should I have hidden the revolver better? That moment has been on my mind a lot,’ said Oey.

Halsema said on Monday that she regarded the part of the house on Herengracht where the gun was kept as a ‘private home’. ‘The fact that this apartment is on the top floor of the official residence does not make the private lives of its residents a subject of public and political debate,’ said a spokesman for the mayor.

But Marianne Poot, leader of Amsterdam’s VVD group, said the issue would be included on the agenda for the council meeting on September 26. ‘I was very surprised when I read it,’ she said of the interview with Oey. ‘I want to have an explanation from the mayor.

‘Why did the mayor call it a replica weapon? I don’t know. I don’t want to speculate because I am sure the mayor is sincere and honest, but it is time for her to give a proper explanation to the council.’

Oey is due to be interviewed by police later this week about why he apparently owned an illegal weapon. He said his wife was unaware that the revolver was in the house until he returned from holiday and admitted it was the same gun his son was found with.

Oey added that he could not rule out there being more illegal items in the house. ‘There are a load of unopened boxes in the cellar of the mayor’s residence. I need to have a good think about what’s all in there. I have boxes with all kinds of equipment in, including a Japanese knife.’