An inmate escaped from a prison work crew Wednesday and is suspected of sexually assaulting a woman at knifepoint and stealing her car a short time later, authorities said.

A manhunt was under way for James Daniel Bird II, 25, who was serving a 15-year sentence on theft and forgery charges. Bird escaped from the 10-man crew working at Warriors Path State Park in Kingsport at about 9:40 a.m. The lone supervisor of the 10-man work crew saw Bird flee on foot.

He was imprisoned at the Carter County Work Camp, a minimum-security annex of the Northeast Correctional Complex.

Authorities said they consider Bird armed and dangerous. "We have the area saturated," said Maj. Harold Owens, with the Sullivan County Sheriff's Department. "We have all our detectives out working on it."

Lt. Lisa Christian with the Sullivan County Sheriff's Department said a woman positively identified Bird as the man who tied her up and sexually assaulted her at knifepoint Wednesday morning. The woman told investigators it took her more than an hour to untie herself and call for help.

The victim told police the suspect also stole jewelry, money, a cell phone and her 1998 red Honda CRV, Tennessee license plate EHA-178.

Bird was described as a 5-foot-11 white male with brown hair, green eyes, tattoos on both shoulders and weighing approximately 160 pounds.

Bird, who began his sentence on Jan. 29, 2000, was to be eligible for parole in February, according to a state database of felony offenders.

Local, county and state authorities were searching for Bird on Wednesday afternoon. An alert was issued for the victim's car and tracking dogs brought in to search the area around Warriors Path State Park, Department of Corrections spokeswoman Amanda Sluss said.

Sullivan County sheriff's deputies said Bird has relatives in the Tri-Cities area.