A Trinity woman and two jailed men were arrested this week after investigators said they conspired to smuggle an opiate into the Pinellas County Jail.

Detectives say Kaitlyn Pergola, 29, concealed suboxone strips behind stamps on envelopes and mailed them to her boyfriend, David Gavin, 30, and his cell mate, Jermonte Rushing, 30, at the detention facility.

Investigators described the suboxone as "heroine in a breath strip," an opiate in the form of a sublingual film. The U.S. Food and Drug Administration says it's a medication  approved for the treatment of opiate dependence.

According to the Pinellas County Sheriff's Office, an investigation was triggered on Aug. 1 when Gavin was being prepared for a transfer to the Jefferson County Jail and began to ask every deputy and jail employee he saw to help him get his mail.

Mail room clerks were asked to inspect Gavin's mail more closely. Four pieces of stamped mail were found addressed to Gavin, and a closer examination revealed small square pieces of orange paper concealed behind each stamp, authorities said.

Gavin was given the contents of the envelopes, but detectives kept the envelopes. They also discovered additional pieces of mail addressed to Gavin, as well as to Rushing. Tests of the "orange paper" revealed the substance to be suboxone, detectives said.

Investigators say they learned Gavin recruited Rushing to have the mail sent to him in exchange for payment and that the two sold the contraband to other inmates. Each stamp sold for $20 and had had five dosage units if cut into strips, detectives said.

Through their investigation, detectives said, Pergola was identified as the source of the suboxone. Detectives said she used two fictitious return addresses that were later connected to her.

Pergola was arrested Monday, and detectives said she admitted to the crime. She was charged with introduction/possession of contraband in a county detention facility, as were Gavin and Rushing.

Since the investigation began, detectives intercepted 11 pieces of mail contained the controlled substance.