OAK HARBOR, Wash. -- An Oak Harbor man accused of molesting and raping 10 young children he met through his job as a youth leader at church entered a plea of not guilty in his first court appearance on Monday.

Nathan Martinez, 21, said nothing while he was in court, but moved his lips continually, as if speaking or singing under his breath.

His attorney pleaded not guilty for him to 30 counts of rape and child molestation.

“Because they are violent sex offenses or class A felonies, if he's convicted as charged, a sentence would include a possibility of a life term,” said Greg Banks, the Island County Prosecutor.

The Island County Prosecutor’s Office filed a new court document Monday after an interview with a 7-year-old girl. She told detectives Martinez wouldn’t let her use her computer until she kissed him and that he kissed girls and boys on the lips.

According to the court documents, she said he did "a lot of not appropriate stuff."

Banks said he may file more charges, but wants to reassure parents of alleged victims.

"My message to them is to take care of their kids and know for the time being, I think, their kids are safe because Mr. Martinez is behind bars," Banks said.

Martinez met his alleged victims through his activities at the Living Faith Christian Center in Oak Harbor.

He babysat the 10 alleged victims, boys and girls, ranging in age from 3 to 13, until one of them complained about Martinez to a parent, Banks said.

Pastors at the church met with Martinez and said he confessed, admitting he could not control his behavior.

“He did mention it was something he wanted to let go and there were times he felt like he was over it, but it would come over him again," said Associate Pastor Fred Burleson.