No felony charges will be filed against a longtime special education teacher at St. Paul's Humboldt Junior High School whom a 14-year-old special education student accused of sexually assaulting her, a spokesman for the Ramsey County attorney's office said Friday.

The teacher remains on paid administrative leave, said Howie Padilla, a spokesman for St. Paul schools.

According to a search warrant affidavit:

The girl, who transferred from Humboldt to Battle Creek Middle School before the 2008-09 school year, told a school social worker that while she attended Humboldt, the teacher would "hit her breast area" when he leaned over her and had shown her pictures of himself as a young adult wearing only underwear.

In an interview with the Midwest Children's Resource Center, the girl said the teacher had once "put her on his desk and sexually assaulted her in his classroom," the affidavit said.

The girl's mother also told police that she had become suspicious of the teacher.

Police searched the teacher's home but found nothing that would substantiate the allegations, spokesman Peter Panos said in October.

Phil Carruthers of the attorney's office said there were no independent witnesses, no corroborating evidence and inconsistencies in the allegations.

While "we hardly ever make the determination that someone's innocent, we just didn't feel there was enough evidence to go forward with prosecution," he said.