DENVER -- A school secretary is on leave after she allegedly bound a child's wrists together and taped his mouth shut.

It happened at Denver's Palmer Elementary School. The boy's mother, Ashlye Tenner, told 7NEWS the school only notified other parents of the situation after she pressed the school to do so.

Tenner said her son was sent to the principal's office for acting up in class prior to being taped up by the secretary. Tenner said her first-grade son, Joshua, is confused by the situation.

"Another teacher came in and saw it and told the secretary, 'You can't do this.' And then the principal came later and told the secretary to take the tape off," said Tenner, who believes the secretary used duct tape.

"I don't understand why a report wasn't made. No one called me. This woman was still at work this morning (Thursday) when I went to the school," said Tenner. "He's my son and I would never tape my son up. Ever. If I did that and he went to his school and told a teacher, it would be considered child abuse."

Tenner said the incident wouldn't be half as bad if the school had handled it properly.

The Denver Police Department is investigating the matter. The Denver Public School District released a two sentence statement calling the incident "very troubling".