A second person has been arrested on suspicion of child abduction in the hunt for a missing mother and her two young children.
Jamie-Leigh Kelly, 31, fled a centre for vulnerable mothers and children in Colindale, north-west London, with her three-year-old daughter and newborn son on Tuesday.
The force said they were “extremely concerned” for the trio as the children are under care protection orders and were removed from the family assessment centre against the wishes of staff.
Police have now found the car and have arrested a 30-year-old woman on suspicion of child abduction. She remains in police custody.
On Wednesday, a man in his 50s arrested in connection with the investigation, on suspicion of child abduction and conspiracy to kidnap, is being questioned by police in Essex.
Detective Superintendent Lewis Basford, who leads the Met’s Public Protection command in East Area, said: “We are making significant progress in our investigation but we remain extremely concerned about the welfare of Jamie-Leigh and her children, one of whom is less than one month old.
“Jamie-Leigh, I continue my direct appeal to you to contact with us so we can ensure the children are safe and well.
“We know you have no intention for the children to come to harm, so we are asking you to please pick up the phone and have a conversation with us so we can meet with you.
“The baby may need medical care as he is newborn, so please put him first and contact us on 020 7175 0793.”
He added: “We believe Jamie-Leigh continues to be assisted, and we ask anyone in Essex or London or further afield who may have information to call our incident room without delay, or dial 999 with any real time sightings.
“If you are helping Jamie-Leigh, it is not too late to do the right thing by the children and contact us.”
Ms Kelly is described as white with green eyes, of slim build and about 5ft 4ins tall.
She was wearing a white jumper or long-sleeved t-shirt, white jogging trousers and white trainers when she was last seen.