SAN ANTONIO -- A South San Antonio Independent School District elementary school principal has been removed from his post in the midst of a sex investigation involving a student, police said.

Michael Alcoser, 41, was recently relieved of his duties at Carrillo Elementary, school district officials said in a letter sent home to parents.

"We do have a reason to believe that there was some kind of a relationship going on, or at least a sexual assault occurring during that time period with the administrator and this one student," said San Antonio Police Department spokesman Sgt. Gabe Trevino.

The boy made the outcry last week after a school district employee told the boy's mother that she thought something wasn't right about the principal's relationship with the boy, Trevino said.

The boy, who is now 13, told police that the alleged relationship began when he was 11 years old attending Price Elementary, where the accused was a vice principal, according to district officials.

The boy said that the school administrator would pull him out of class and lunch and take him to his office, where the educator would fondle the boy and take pictures of him in his underwear, Trevino said.

The boy said that in another incident the administrator took the student to his home, where he performed oral sex and took pictures and video of the boy in a Speedo, Trevino said.

Police searched the principal's home over the weekend and recovered pictures, a computer and other equipment, Trevino said.

"We also recovered some evidence from the administrator's office at the school," Trevino said.

The case is currently under investigation, Trevino said.

Police are working with district officials to determine whether there could be other victims, Trevino said.