UPDATE: An Allegheny County teen wanted by police turned himself in Sunday night.

The suspect, Alex Lamont Boyden II, 18, of McKees Rocks is being held in the Butler County Prison without bail.

Jackson Township police have a felony arrest warrant for a teenager they say held a knife to a woman's neck and threatened to kill her, cut her on the hand, and choked her until she blacked out during an altercation Saturday along a dead end road.

Boyden allegedly left the injured woman along the road and drove away in her car. He is accused of attempted homicide and other charges.

The victim, a McKees Rocks woman, sought help from a passing motorist.

She was eventually taken by an ambulance to a Pittsburgh hospital for treatment of injuries. Her condition was not known Sunday.

The good Samaritan called 911 Saturday evening after he reported seeing the woman in trouble along Tollgate School Road and bleeding from a cut on her left hand.

The woman gave police a harrowing account of her ordeal that began after she had earlier picked up the defendant, a friend, at a home in Kennedy Township, Allegheny County.

She drove to several convenience stores, and they eventually changed seats.

Boyden drove onto Interstate 79 and headed north for an “extended period,” the woman recounted. She became “nervous,” police, and asked him to turn around. But he refused.

The woman told investigators the defendant at some point turned down a dirt/gravel road that stops at an embankment below the interstate off-ramp. Police later identified the road as Perry Way.

The defendant allegedly suggested they “hang out” there, which made the victim uncomfortable, police said. Boyden eventually got a metal knife and held it to her neck.

When she tried to take the knife away, a struggle ensued, police said, during which she was cut between the thumb and index finger on the left hand.

The defendant continued to threaten her, she said. Later, they both got out of the car from the passenger side door.

Boyden, still holding the knife, is accused of walking the woman to a nearby grassy hillside. He allegedly pushed her down and again held the knife to her neck, repeatedly telling her, “I'm going to kill you” and, “Tell me what you know,” according to charging documents.

The woman told police that she did not know what Boyden wanted her to tell him. She recounted he then strangled her.

“During this time,” documents said, “(the woman) felt that she was going to die, as she remembered not being able to breathe, then blacking out.”

She eventually regained consciousness and heard the defendant calling her name. She said she asked him to take her to the hospital, but he refused.

He subsequently ran to her car and drove off, police said, but not before telling her to “lay there and die.”

Authorities described the car as a black, 2001 Mercedes-Benz convertible with the Pennsylvania license plate LC-8761.

Boyden was last seen traveling north on Route 19, and police said a license plate reading system indicated the car passed through Main and East New Castle streets in Zelienople.

Boyden is described as black, 6'3" tall, 175 pounds with black hair and brown eyes.

This is a breaking news story. The Eagle will update this post with any developments. To read the full story, make sure to pick up Tuesday's edition or subscribe online.