Three people face federal charges for allegedly conspiring to take two young girls to an Indiana hotel room for a sex "party," then taking pictures as the children were molested.

Tabitha D. Robinson, 32, of Midlothian allegedly took a 3-year-old girl to a Best Western in Terre Haute, Ind., in August to meet two people she had "an online relationship" with, knowing the child would be molested, according to the complaint filed this week in U.S. District Court in southern Illinois.

William M. Milligan, 27, of Bloomington, Ind., allegedly e-mailed Robinson driving directions to Terre Haute on Aug. 7 with a subject line that said "map to the party lol," the abbreviation for "laughing out loud."

Prosecutors say Robinson's camera was used to take nude pictures of the 3-year-old and an 11-year-old girl being cared for by Louise Helen Masulla, 32, of New Athens.

Investigators found images on computers owned by Robinson and Masulla of the girls "engaging in sexually explicit conduct" with Masulla in the hotel room, the complaint said. Robinson allegedly admitted e-mailing video of sexual acts involving the younger girl to Milligan.

"Our message to child predators is this: If you exploit children, we will find you and we will prosecute you," A. Courtney Cox, U.S. attorney for the Southern District of Illinois, told The (Bloomington) Pantagraph.

Robinson, Masulla, and Milligan are charged with conspiracy to produce child pornography and conspiracy to transport minors to engage in criminal sexual activity. Masulla is also charged with aggravated sexual abuse and transportation, and Milligan is charged with receipt of child pornography.

The offenses carry prison terms that range from five years to life.

It was not clear if those charged have attorneys. There were no telephone listings for Robinson in Midlothian and Masulla in New Athens, and no one answered the phone at a number for Milligan.

The conduct was exposed after an investigation by Alton police that resulted in five counts of predatory criminal sexual assault against Masulla, investigators said. She allegedly implicated Robinson, according to the complaint.

The Illinois Department of Children and Family Services has opened an investigation, spokesman Kendall Marlowe told the Chicago Tribune. He declined to say whether any children were taken from Robinson's home.

The case was investigated by the Springfield, Chicago, and Indianapolis offices of the FBI, Alton Police, the Illinois State Police and the Cook County Sheriff's Police Department. The U.S. Attorney's office for the Southern District of Indiana helped investigate Milligan.