Former Penn State assistant football coach Jerry Sandusky leaves the Centre County Courthouse after the first day of his trial in Bellefonte, Pa., Monday, June 11, 2012. He is accused of 52 counts of child sexual abuse involving 10 boys over a period of 15 years. (AP Photo/Gene J. Puskar)

BELLEFONTE, Pa. - The teenager whose report of sexual contact with Jerry Sandusky led to a grand jury investigation tearfully told jurors Tuesday the former Penn State assistant football coach performed oral sex on him after meeting him through his charity for at-risk youth.

The accuser, known in court documents as Victim 1, broke down as prosecutors questioned him about the encounters. Sandusky faces 52 criminal counts related to the alleged assaults of 10 boys during a 15-year period. Authorities allege Sandusky abused boys at his home and inside the football team's facilities, among other places. Sandusky denies the charges.

Now 18, the witness said he frequently spent the night at Sandusky's home, and on one occasion the coach performed oral sex on him after lying on top of him to "crack" his back.

"After kissing my forehead and cheek, he moved to my lips," the teen said. "He kissed my lips, then he moved to my back again. ... Then he started to rub underneath my shorts."

The teen told the jury Sandusky would also initiate contact by blowing on his stomach and performed oral sex on him.

"I didn't know what to do with all the thoughts running through my head, I just kind of blacked out and didn't want it to happen. I froze," the alleged victim said.

Sandusky didn't visibly react to the teen's account and looked straight ahead during his testimony.

The charges against Sandusky — and two university officials accused of perjury and failing to report suspected child abuse — touched off a massive scandal that led to the firing of legendary football coach Joe Paterno and the departure of the university president. Paterno died in January of lung cancer.

The earliest of Sandusky's alleged victims testified Monday, the trial's opening day, telling jurors that the former assistant coach sent him "creepy love letters" and made him sign contracts that would pay him money for spending time together.

The man said he began showering with Sandusky in 1997 and what started out as "soap battles" quickly escalated to sexual contact, including oral sex.

Lead prosecutor Joseph McGettigan III has described Sandusky as a "serial predator" who methodically used his youth charity, The Second Mile, to zero in on fatherless children or those with unstable home lives, buy them gifts and take advantage of them sexually.

Sandusky lawyer Joe Amendola countered that the case is flimsy and that some of the accusers apparently intend to sue and have a financial stake in the case — a preview of the battle to come as the defence tries to undermine the credibility of the young men upon whom the case rests.

News from © The Associated Press, 2012