(CNN) Starbucks is apologizing after a California sheriff's office said two of its deputies were ignored in a store.

"Two of our deputies were refused service at Starbucks," Riverside County Sheriff Chad Bianco said on Twitter. "The anti police culture repeatedly displayed by Starbucks employees must end."

The department said on Twitter on Friday it was aware of the "cop with no coffee" incident that took place Thursday night.

Starbucks spokesman Reggie Borges told CNN the deputies were ignored for nearly five minutes -- and there's no excuse for that.

"We are deeply sorry and reached out to apologize directly to them. We take full responsibility for any intentional or unintentional disrespect shown to law enforcement on whom we depend every day to keep our stores and communities safe," Borges said.