Marta, who is 14, was last seen with her sister Lidia (17) around the Broadway Street/Ashton Road area in Oldham on Friday evening.
Marta is described as a white female who was wearing black Adidas leggings with stripes down the leg.
She was wearing a cropped black Adidas t-shirt, a black puffer coat and white Nike Airforce trainers.
Lidia (above) is 5ft, 5in tall and of slim build with long, dark hair.
She sometimes wears wigs.
If you have any information about where Marta and Lidia are, please call Greater Manchester Police on 101 or 0161 856 1382 and 0161 856 8931.
