LA HABRA — Police cited six people for providing alcohol to minors and arrested or cited four others on other charges during a “decoy shoulder-tap” sting operation Friday, ahead of the St. Patrick’s Day holiday, authorities said.

The operation was part of a statewide operation, the largest-ever of its kind — involving the California Department of Alcohol Beverage Control and 90 law enforcement agencies throughout the state, La Habra police officials said in a written statement.

A total of 21 people were contacted by underage decoys working with police to approach people outside convenience stores and ask them to purchase alcohol for them, police said.

“The minor indicates in some way that he or she is underage and cannot purchase the alcohol,” according to the police statement.

Six people were cited for furnishing alcoholic beverages to minors, one person was cites for possession of graffiti tools, one person was cited for possession of marijuana and two people were jailed due to outstanding warrants, officials said.

The penalty for furnishing alcohol to minor includes a minimum fine of $1,000 and 24 hours of community service.