Wichita ? Authorities have solved a telephone mystery at the Sedgwick County Jail, and theft charges could follow.

In late January, about two dozen people reported being billed as much as $164 for collect calls from the jail  calls they did not accept.

The problem has been solved, and AT&T will reimburse those wrongly billed, phone company spokeswoman Suzanne Keough said. She said incorrectly coded phones in the jail were to blame for the third-party billing.

Collect calls from inmates are supposed to automatically end if the recipient tries to use three-way calling or forward calls to a third party for billing.

However, inmates calling from some of the jail’s phones were able to bypass that restriction because the AT&T system recognized the phones as regular pay phones instead of jail phones, Keough said.

At least three phones in one of the housing units were involved, said Iris Baker, Sedgwick County purchasing director.

Sedgwick County Sheriff’s Capt. Greg Schauner said criminal charges, possibly for theft, could be filed if investigators are able to determine which inmates made the calls.

“It’s reasonable to assume that they knew full well what they were doing,” he said.

Schauner said investigators are examining about 6,000 phone calls made from those jail phones during the past four to five months and also are checking to see whether other third parties had been billed for similar calls.

The bills, which identify the recipients of the phone calls, have been turned over to the district attorney’s consumer fraud division, Baker said.

Sedgwick County Sheriff’s Capt. David Thompson said inmates remain unable to place international calls, a process that may have been part of the problem.

International calls were blocked after the third-party billing problem arose, on the chance that inmates were causing the problem while placing such calls.