More information on the arrest won't be available until the police report is completed in a few days, according to UMKC Police.
Callaspo was not available for comment Friday before the game. Royals manager Trey Hillman said he discussed the incident at length with his player.
"We're still gathering as much information as we can," Hillman said, "and beyond that, I don't have too much to say, other than it was an unfortunate incident and we're going to handle it internally as soon as we've collected all the facts."
This isn't Callaspo's first run-in with the law. Last May, when Callaspo was with the Diamondbacks, he was arrested on suspicion of misdemeanor assault of his wife and felony criminal damage.
He was reinstated to the D-backs nine days later and played the rest of 2007 with Arizona. The Royals acquired him in a trade for pitcher Billy Buckner during the offseason. Callaspo has played primarily as a pinch-hitter or defensive replacement this season at second base, shortstop or left field. He's hitting .290 with four RBIs in 100 at-bats this year.
"It's certainly a regrettable situation, very unfortunate," general manager Dayton Moore said. "I know Alberto is very remorseful, he's embarrassed, he's scared. And we're very supportive of getting him through this tough time."
Mark Dent is an associate reporter for MLB.com This story was not subject to the approval of Major League Baseball or its clubs.