The disappearance of a woman and her two-year-old daughter is now being treated as a murder investigation, Police Scotland has said.
Avon and Somerset Police issued an appeal last week to trace 25-year-old Bennylyn Burke and two children from South Gloucestershire.
A man, 50, was arrested on Friday at a property in Troon Avenue, Dundee.
He has been charged in connection with the deaths of Ms Burke and her daughter Jellica.
Police said inquiries are ongoing to establish their whereabouts.
The second child reported missing has been traced and is being supported, the force added.
Det Supt Graeme Mackie, from the force’s major investigation team, said: “We are now treating the disappearances as a murder investigation and I would urge anyone with any information to please come forward and speak to us.
“This is a complex enquiry involving both local officers in Dundee and specialist resources from across Police Scotland.
“Bennylyn’s next of kin have been updated on the arrest and are being supported by colleagues from Avon and Somerset Police.
“Our thoughts are with her family and friends at this very difficult time.
“There will be an increased police presence in the area for a considerable period of time and I would like to thank the local community for their cooperation.”
Det Supt Mackie asked anyone with information to speak to local officers or to call Police Scotland via 101.
The arrested man is expected to appear at Dundee Sheriff Court on Monday.
Ms Burke and two children were reported missing on 1 March. Avon and Somerset Police put out an appeal for information two days later.
The force said the 25-year-old was last seen at her South Gloucestershire home on 17 February.
Officers in Dundee attended the property in Troon Avenue at around 15:20 GMT on Friday.
There was a large police presence around the property, which is near Downfield in the north of Dundee, with dozens of police and forensic officers at the scene.
Police Scotland closed off the street with a cordon around the house.
A blue tent has also been erected in the front garden to cover a waste skip and yellow polythene has been used to cover windows at the back of the property.