A college student was video chatting on her cellphone and driving nearly 100 mph when a trooper pulled her over on a busy highway near St. Peter, Minn., according to the State Patrol.

Theresa M. Redenius, 18, of Lakeville, “laughed and was flippant” in front of the trooper after being stopped about 12:30 p.m. Saturday on southbound Hwy. 169, according to the citation charging her in Nicollet County District Court with careless driving.

Redenius on Thursday acknowledged not knowing how fast she was going but contended she was using her phone correctly while heading back to school at Minnesota State University Mankato.

The State Patrol used her case to caution its 43,000 followers on Twitter this week that “extra distracted driving enforcement is now on MN roads.”

According to the citation, trooper Gabriel Cornish wrote that he saw the SUV coming up from behind him “flying in the left lane very fast.”

He used his rear radar detector on his marked squad car and clocked the SUV approaching at 96 miles per hour.

Cornish said that she apologized and “smiled while I explained the gravity of everything and quickly wanted to get going and jumped right back on her phone as I turned to go back and run her license.”

Redenius explained in a text Thursday, “I did not know I was going that fast and was just going with the traffic around me” on the four-lane highway about 5 miles south of St. Peter.

As for her response to the trooper’s roadside message about driving safely, she said, “I did take it seriously and wasn’t giggling.”

Redenius’ first chance to tell her side to a judge comes at her arraignment on May 1.