Leon Williamson, 12 and Olivia Bryson, 14, were last seen around 9:15am on Tuesday 22 May 2018, at Glengarnock Train Station.
Both children live in residential accommodation in the Ayrshire area.
Leon is around 5 ft. inches tall with a stocky build, brown short hair and blue eyes.
When last seen, he was wearing grey coloured jogging trousers, a white polo shirt, dark jumper and green trainers. He has a Scottish accent.
Olivia is around 5 ft. 2 inches in height, with a medium build, blue eyes, freckles and brown hair normally worn in ponytail.
She was wearing dark coloured jogging trousers, a North Face jacket, which is grey coloured at the top and dark coloured at the bottom.
Olivia tends to wear a black baseball cap on her head with her jacket hood up. She has an English accent.
Enquiries carried out so far have indicated that Leon and Olivia boarded a train and have travelled to Manchester. Olivia does have family there so it’s possible she has gone to visit them.
Officers are liaising closely with other officers from British Transport Police and Greater Manchester Police. Officers are checking out a potential sighting of them at Whitworth Park in Manchester.
Sergeant Allen Dodds said:
“Our concern is growing for both Leon and Olivia, they are both young children and we need to know they are safe and well. We are liaising with our counterparts for any information which could assist us in locating Leon and Olivia. We are currently checking out a potential sighting of them in Whitworth Park in Manchester. However, I am appealing to anyone who may have seen them or who has any knowledge as to their whereabouts to contact us.”
Anyone with information is asked to call officers at Irvine Police Station via 101, quoting incident number 0795 of 22 May 2018.