JACKSONVILLE, Fla. -

Christopher Bacca was formally charged Wednesday with four counts of capital sexual battery and four counts of lewd and lascivious conduct involving a child. He pleaded not guilty.

The 26-year-old former teacher at Windy Hill Elementary School was arrested last month, accused of molesting a boy in his home.

Police reports show Bacca showered with a boy, who police said slept in his bed before the assault. The boy also told police that Bacca showered with him and performed oral sex on him more than once.

Prosecutors say all the incidents occurred with the same boy, and they don't believe there were any other victims.

"Obviously, children under the age of 12 are our most vulnerable victims," Assistant State Attorney Theresa Simak said. "And so there is probably nothing more important than protecting those children. And this kind of case is always difficult and serious, and it's important to the community as well as just the individual victims."

Bacca is being held without bail. His next scheduled hearing is Sept. 13.

In a separate ongoing investigation, Duval County schools are investigating how Bacca wound up teaching in an elementary school within months after a Florida Department of Children and Families inquiry into previous accusations that Bacca was having inappropriate contact with a child during as previous teaching job.

Bacca was reprimanded at Long Branch Elementary School, accused of "grooming" a child he had a "special relationship" with.

During an investigation, a forensic analyst determined the student viewed pornography from Bacca's computer during his pre-planning period. But because investigators found no evidence of a sexual relationship, no criminal case was filed.

Bacca continued teaching but transferred to Windy Hill, which has many parents outraged, especially the mother of the boy police say Bacca took advantage of.

"It was a breach of trust with a teacher," said A. Wellington Barlow, the attorney for the child. "Think about it. Teachers spend more time in a day than parents do. So this man had access to a lady's child. So she's very, very devastated about it."

"Obviously, they have access to children, so it's extremely important that we can entrust the teachers that are in the classroom with our children not to be child molesters," Simak said.