A 48-year-old man has been arrested following a sex attack on Brighouse canal towpath.
Police said the man was arrested locally on suspicion of sexual assault following the attack, at 6.45am on Tuesday.
CCTV images which appeared to show a man running along the the canal towpath beside the Calder and Hebble Navigation were released this morning.
The 22-year-old victim has been interviewed by specialist officers.
The man is currently in custody for questioning, police said.
Anyone with information should call Calderdale CID via 101 or Crimestoppers on 0800 555 111.