ST. AUGUSTINE, Fla. -- The St. Johns County Sheriff's Office found the 35-year-old sex offender on Sunday after he had removed his GPS tracking device last week.

The St. Johns County Sheriff's Office said on Facebook that they "were able to take him into custody without incident and with no injuries to any of our deputies on scene."

Robert Ferrell, 35, failed to register as a sex offender after being released from prison in July, the Sheriff's Office said. Ferrell removed his GPS tracking device and threw it in a trash can along U.S. 1 in St. Augustine.

Commander Chuck Mulligan said tracking sex offenders like Ferrell is far from an easy job.

"It does create for a lot of workload in knowing where these individuals are," Mulligan said.

While the state contracts with private companies for GPS tracking of sexual offenders, Mulligan said it's the Sheriff's Offices' responsibility to keep tabs on them. That means regular, random check-ins to make sure they're staying where they need to be.

What makes it difficult is when they run.

"At any particular moment, if one of them decides to abscond, that's something they're going to do in a 10 or 15 minute period, very difficult to be able to know exactly where they are at that time," Mulligan said.

According to authorities, Ferrell lived in the woods near State Road 16 and Interstate 95. Those without resources or money are legally allowed to do so, but it means GPS trackers need set coordinates. In Ferrell's case, areas around the woods which Ferrell cannot leave.

It's not the first time an offender has removed a tracker. Aside from inserting a tracking chip into the body, which is not yet legal, GPS trackers are the best option right now.

"We're certainly not at a point in this country where we are installing chips in people's particular body parts, where some sort of invasive procedure would need to be done in order to extract that," Mulligan said.

St. Johns County residents can look here to see what sex offenders live nearby.