MILWAUKEE (CBS 58) -- A 33-year-old Milwaukee Public Schools staff member is accused of sexually assaulting students at Oliver Wendell Holmes School. 

Randell Jefferson faces the following charges: 

• Second degree sexual assault of a child
• Child enticement (3 counts) 
• Soliciting a child for prostitution (3 counts) 
• Exposing a child to harmful material (3 counts) 

Jefferson is listed under the MPS staff directory as a 6th grade substitute teacher. 

According to a criminal complaint, over the course of two years, Jefferson pressured students to perform oral sex on him on multiple occasions. 

The complaint says Jefferson would offer the victims money or gifts in exchange for sexual acts. 

Investigators identified four potential victims who disclosed sexual harassment by Jefferson and say all of the assaults occurred at the school. 

Jefferson is due in court on May 15.