ALBANY, Ore. -- Two separate videos of two teenage girls having sex with an 18-year-old boy were found on the seized laptop of another 18-year-old boy, according to the Linn County Sheriff's Office.

The girls, who were 16 and 17 at the time the recordings were made, were unaware they had been filmed until detectives told them.

The investigation started with a tip from a Linn County teen who heard rumors of the video's existence and called the sheriff's office with information. Based on that phone call, detectives contacted Jesse Thomas Strickland, 18, of Albany, who consented to a search of his laptop computer, according to the sheriff's office.

Detectives located two separate videos on Strickland's computer showing another teen, Andrew James Pigg, having sex with the two girls.

Investigators believe Pigg secretly recorded the girls using a camera built into the lid of the laptop computer. The videos, each about 40 minutes in length, show Pigg (and Strickland in one of the videos) setting up the camera, according to the sheriff's office.

It is still unknown if the videos were distributed electronically to others or how many people may have viewed the videos before the laptop was seized, according to the sheriff's office.

Pigg was charged with:

• Two felony counts of using a child in display of sexually explicit conduct
• Felony encouraging child sexual abuse in the first degree
• Invasion of personal privacy
• Tampering with a witness

Strickland was charged with:

• Using a child in display of sexually explicit conduct
• Encouraging child sexual abuse in the first degree
• Invasion of personal privacy

Both suspects posted bail and were released from the Linn County Jail, according to the sheriff's office.

The Sheriff's Office is withholding the identities of the minor victims.  The investigation is continuing.