Police in Minneapolis, St. Louis Park and Woodbury are looking for two suspects they say have been skimming credit cards at the self-checkout registers of area grocery stores.

One of the card-skimming devices was found at a Lund’s and Byerly’s store, at 25 SE University Av., on Feb. 7 by store employees, who turned it over to a police officer who was working off-duty there, according to a police report. Store staff told the officer that similar devices had been discovered at other locations, including the Lunds and Byerly’s at St. Louis Park and Woodbury, the report said.

Surveillance footage showed a man and woman installing the device over one of the registers, while trying to conceal their actions from other customers, store employees and a nearby camera, the report said. Investigators have been reviewing the video to identify the two suspects involved, it said.

The status of the cases in Woodbury and St. Louis Park was not immediately known on Wednesday.

No arrests have yet been announced in the case.