Republican candidate for governor Jeff Johnson reported that a 15-year-old DFL Party volunteer entered the Duluth home of his running mate over the weekend, saying he needed to call for a ride because his cellphone had died.

Johnson related the incident Wednesday on Twitter. His running mate, Donna Bergstrom, wasn’t home when the teenager knocked on her door, Johnson said. Her husband let him in, not knowing who he was. When Bergstrom returned home, the person was sitting on the couch chatting with her husband and 13-year-old son.

Johnson suggested the person was a tracker for the DFL. Trackers are typically young party operatives who follow opposing candidates to public events and record them, hoping to catch a “gotcha” moment.

But state DFL Chair Ken Martin, who quickly apologized for the incident, later said the individual had been identified as a teenage student intern who has volunteered for several campaigns but has not worked as a tracker for the party.

Johnson called the conduct “absolutely unacceptable,” but said he wouldn’t release the name of the individual or take further action. “To actually enter someone’s home under false pretenses is a new low,” Johnson wrote. He pledged that if anything like this happens again, “the police will be involved.”

Martin agreed that the action was unacceptable. “None of our DFL employees are encouraged to act in this way, and receive training on how to be respectful in their job at all times,” he said.

“No candidate for public office should have to worry about this kind of unacceptable intrusion in the privacy of their own home,” Martin said, adding that he had called Johnson personally to apologize for the incident.

Party spokeswoman Charlene Briner said Thursday the 15-year-old had been at a DFL event and walked to the home of his friend to call his dad for a ride. His friend wasn’t home, he knew the Bergstroms lived across the street and knocked on the door, she said.

Briner described the teenager as “enthusiastic” but said “he made a bad mistake.