HIGHLANDS RANCH, Colo. – The head football coach at Highlands Ranch High School abruptly resigned from his position following a suspicious incident during a routine drug sweep of the school’s parking lot.

Mark Robinson submitted his resignation last Friday after more than three years with the Douglas County School District. He told school officials and parents in his resignation letter that he was “slipping” in his duties as head coach, but his alleged behavior during the sweep conducted by Douglas County deputies the previous day is telling.

An incident report obtained by Denver7 states Robinson drove a player’s car away from the school’s parking lot on Aug. 24 just moments after he was informed by deputies that a K-9 unit was on their way to the school to conduct a drug sweep of the parking lot.

The report goes on to state that two school security officers told a Douglas County Sheriff’s Office they saw Robinson drive off in one of his student’s vehicles and told them he was leaving for a moment to put gas in the student’s car and would be back.

But when Robinson returned, the car was no longer with him.

At that point, the deputy who was at the school with his K-9 unit was told the car was parked in front of Robinson’s home, which is located just south of the high school, according to the sheriff’s office report.

The deputy then called his sergeant who told him to run the K-9 unit around the student’s car. The K-9 sniffed around the vehicle and “there was a positive hit,” the report states.

The deputy then asked to speak to the student, so that he could get consent to have the K-9 search the vehicle.

According to the report, the student told the deputy he left his car at his house that morning, but said he could not remember what street he lived on.

The deputy then told the student the car was parked on the street behind the school and the student replied, “Yeah, that’s coach’s house.”

The student then said he had given his keys to coach Robinson earlier that morning and that he wasn’t sure at what time that happened, but that Robinson took his car to get him “some personal items like shoes or clothes or something,” according to the report.

After the student was informed a K-9 had a positive hit on his car, the boy told the deputy he did not want to have his vehicle searched because he “just doesn’t like cops like that,” the report states.

The student was allowed to return to class and no charges were filed in this case.

Robinson was hired by the Douglas County School District in March 2014 and became head football coach later that year.

“I can confirm that Mark Robinson is no longer the football coach at Highlands Ranch High School. Further, he is no longer employed by the Douglas County School District,” said Nate Jones, a spokesperson for the school district, Friday evening.

Robinson was suspended in 2015 for violating league rules.

The Highlands Ranch Falcons are scheduled to play the Cherokee Trail Cougars at Shea Stadium in Highlands Ranch at 7 p.m.