A 15-year-old girl was a victim of upskirting after a man took photos under her school skirt, police have said.
The man allegedly followed her into Sainsbury's at Manchester Piccadilly station at 16:30 BST on 1 April.
British Transport Police (BTP) said he made "multiple attempts" to place his phone under her skirt and succeeded as she queued at a till.
The force has issued CCTV images of a man they want to speak to.
He is urged to come forward and is appealing for anyone who recognises him to contact them.
Upskirting became a criminal offence earlier this month with offenders facing up to two years in prison for taking a photo under somebody's clothing.