Portland police have cited three city retailers for selling alcohol to minors during a sting operation between March 4 and March 11.

Police worked with underage students from Southern Maine Community College to conduct checks at 68 stores to see if they would sell alcohol to minors under the age of 21, according to a news release.

The three businesses that were cited were issued summonses. They are City Beverage, 1 Exchange St.; Riverside Gas, 1585 Forest Ave.; and Three D’s Variety, 885 Brighton Ave.

The 65 establishments that passed the compliance checks represent a high compliance rate, according to the city, and will be notified by mail beginning today as to the date and time they were checked.