Joyce Mitchell, the prison tailoring shop instructor charged with helping two killers flee from an upstate New York prison, is expected to appear in court today as the search for the convicts enters its 10th day.

Mitchell, 51, is charged with promoting prison contraband and criminal facilitation for allegedly helping inmates Richard Matt and David Sweat escape from Clinton Correctional Facility in Dannemora, New York, on June 6.

According to Clinton County District Attorney Andrew Wylie, Mitchell had planned to meet Matt, 48, and Sweat, 35, at a power plant near the prison the night of their escape and expected to drive them to a wooded area about seven hours away.

Instead of driving the getaway car, Mitchell checked herself into a hospital, complaining of a panic attack, Wylie said.

“She realized what this was going to do to her family,” Wiley said. “She realized that she loved her husband, Lyle, and she did not want to leave him at the end.”

Mitchell has pleaded not guilty.

Authorities say the escape was being planned for five weeks. According to prosecutors, Mitchell smuggled speed-bag boxing gloves and lighted glasses, along with blades, chisels and cutting tools into the facility.

The convicts used power tools to cut through the back of their adjacent cells, broke through a brick wall, then cut into a steam pipe and slithered through it, finally emerging outside the prison walls through a manhole, authorities said.

Matt was serving 25 years to life in prison after he kidnapped and beat a man to death in 1997. Sweat was serving a life sentence after he was convicted of killing a Broome County sheriff’s deputy in 2002.

Authorities remain unsure where the inmates might be.

“We don’t know if they are still in the area, of if they’re in Mexico by now,” New York Gov. Andrew Cuomo said.

Cuomo this morning announced a formal investigation “to determine all factors potentially involved in the escape,” according to a press release. New York Inspector General Catherine Leahy Scott is tasked with conducting the investigation.

“Capturing these killers and returning them to state custody remains our top priority – however, it’s critically important to examine the circumstances that enabled these inmates to escape in the first place,” Cuomo said in the press release.

The Associated Press contributed to this report. Source: ABC News Worker to Appear in Court as Search for Convicts Continues