A massive manhunt is under way after a father abducted his three-year-old son from foster parents.
Robert Gurling is only allowed contact with his son under supervision but abducted the youngster, Essex Police said.
They were last seen in Great Notley near Braintree in Essex at about 10.30am on Saturday.
Police search teams and a helicopter have been combing the area in an "urgent" search for the pair but have not found them.
Detectives are appealing to the public to help trace Mr Gurling, who is described as white, aged in his 40s, 6ft tall and of medium build.
He has cropped dark brown greying hair and was wearing a grey tracksuit top and jeans.
The boy has blonde hair and was wearing a jacket, grey tracksuit bottoms and red trainers.
They may be travelling in a blue car.
Detective Chief Inspector Simon Werrett said: "Mr Gurling has abducted his child from the foster parents.
"He is not allowed unsupervised access to the child and therefore we need to urgently locate the child to ensure he is safe and well.
"Anyone who sees them should phone 999 immediately. Anyone with less urgent information about their whereabouts should call Essex Police on 01245 282103."