Police have launched an appeal to trace singer Sinead O'Connor after she was reported missing.
The 49-year-old Irish star has not been seen since she went on a bike ride at 6am on Sunday in the Chicago suburb of Wilmette.
In a statement, Wilmette police said it was "seeking to check the well-being" of the musician.
A force spokesman said: "O'Connor reportedly left the Wilmette area for a bicycle ride yesterday at 6am and has not returned.
"A caller has expressed concern for her well-being and no other information is available at this time."