Now-suspended professor Sergey Macheret was arrested in Lafayette Wednesday after a sting operation led to him being preliminarily charged with dealing and possession of methamphetamine and unlawful proposition.
Unlawful proposition under Indiana's criminal code is paying or offering to pay for sex.
Lafayette police pulled the aeronautics and astronautics professor over in a traffic stop around noon after an undercover police officer talked to him at the intersection of 18th and Union streets, an LPD press release reads.
LPD had been investigating Macheret, 65, since December after getting multiple reports of a "suspicious male approaching women."
Macheret was given a $500 bond and bonded out of jail by Wednesday night, Tippecanoe County jail logs show.
Talk of Macheret's arrest began swirling online Wednesday evening after a student posted to Reddit about him not being in class and another account responded with his arrest information from the jail logs.
Purdue said in an email to students that the professor was placed on leave "effective immediately" after his arrest and is working to make sure his "undergraduate and graduate students needs are met."
Department head Bill Crossley wrote in the email that he encourages students and employees to use the mental health resources available that they might need regarding the situation.