Lincolnshire Police have issued an appeal to find 24-year-old Vytautas Baltrukonis, who has been missing for almost a week.
Baltrukonis was last seen when he attended Lincoln County Hospital for an appointment on the evening of Friday, February 13. Staff at the hospital later reported him missing.
It is believed he may still be in Lincoln.
Officers say they are concerned for his welfare and would like to hear from anyone who may have seen him.
He was last seen wearing a white booble hat that has a red band with white ear flaps and tassles, a green zipped hooded coat, a blue fleece, grey gloves, dark grey trousers, black shoes, and a white or beige coloured scarf. He is around 5ft 7in in height and of slim build.
Anyone who has seen Mr Baltrukonis or knows of his whereabouts should contact Lincolnshire Police on 101.