Oliver Malkin, 12, was snatched by his father Peter, 54, as he stepped off a school bus near his home in Landevant, Brittany, on Monday.
Solicitors acting for Oliver's mother, Eliza Pridmore, 36, served orders on four people to appear in court yesterday in the hope that they could shed some light on where Mr Malkin has taken his son.
At a private hearing, Mr Malkin's brother Anthony, 58, went into the witness box to be questioned. He was followed by Jeremy Warner, manager of Peter Malkin's Bridge Place Country Club in Canterbury, Kent, and Len Widnall and John Rice, former club employees.
The judge, Sir Stephen Brown, President of Family Division, said afterwards: 'These persons . . . have each given solemn undertakings to the court to notify the police, the Official Solicitor, who represents Oliver, and the mother's solicitors of any information which may come to them.'Reuse content