St. Louis, MO (KTVI) -- St. Louis County Police are scratching their heads, but praising their officer, after a bizarre incident Monday afternoon on I-44. Video sent to the Fox 2 Newsroom by a passing motorist shows the end of the ordeal as a woman was tased by an officer after she tried to jump into oncoming traffic.

According to St. Louis County Police Officer Brian Schellman, around 4 p.m. Monday, an officer was westbound on I-44 when he spotted a woman pass him at an estimated 85 mph. As she passed, she had her arm out the window of her car and was flashing the officer an obscene gesture. The officer put on his emergency lights and gave chase. Police say the woman immediately slammed on her brakes and stopped the car on I-44, causing three cars behind her to swerve and avoid a crash.

Police say the woman exited her car and began to run down the interstate while singing the national anthem. The police officer gave chase on foot, yelling for her to stop. Police tell us she stopped and began yelling "Martin Luther King" at the officer, before jumping into the path of an oncoming car. The car swerved to avoid her, and the officer drew his taser gun and tased her to the ground.

This afternoon, police still don't know the motive for the woman's actions. She's a 42 year old Texas resident who is currently at a local hospital getting a psychiatric evaluation. No charges have been filed yet.