A 30-year-old man has been arrested in the killing of Jennifer Whipkey, 22, who was found stabbed in the woods behind a West Deptford motel more than six years ago.

Investigators think Brian Mertz of West Deptford met Whipkey outside a nightclub on May 25, 2002, then raped and killed her before abandoning her body. Mertz was charged Sunday with first-degree murder, first-degree felony murder, and aggravated sexual assault.

At a news conference yesterday at the Gloucester County Prosecutor's Office, Whipkey's mother, Elizabeth McCool of East Greenwich, thanked law enforcement agencies for their work.

"Today I stand here grateful," she said. "We have waited a long time for this day and could not have received a better gift this Christmas than to see the person responsible for Jen's murder brought to justice."

Mertz was held at the Gloucester County jail with bail set at $750,000. No court appearance had been scheduled.

A DNA sample taken from Mertz matches DNA found on Whipkey's body, Gloucester County Prosecutor Sean Dalton said. He declined to say how authorities obtained Mertz's DNA or how they initially connected Mertz to the killing.

Whipkey, also of East Greenwich, attended Kingsway Regional High School and worked at Brothers Pizza in Paulsboro. She had enlisted in the Air Force National Guard shortly before she was killed and had dreams of becoming an air-traffic controller, according to her family.

"She was full of life," her mother said yesterday. "She loved people. She was a trusting, generous, warm-hearted woman."

Whipkey also was devoted to her daughter, Alissa, who was 4 when her mother was killed. Whipkey and Alissa's father, Adam Whipkey, divorced about a year before Jennifer Whipkey's death, but remained friends. Alissa is being raised by her father as well as by McCool, said Bernie Weisenfeld, a spokesman for the Prosecutor's Office.

Whipkey disappeared on Memorial Day weekend in 2002 after a night out dancing with friends at the Adelphia Restaurant in Deptford.

She was last seen about 3 a.m. in the parking lot after the club closed, standing with a group of five or six men, authorities said.

A newspaper deliveryman came across Whipkey's body shortly before noon the next day in the woods behind the Westwood Motor Lodge in West Deptford. She had been raped and stabbed in the throat, head, chest, abdomen and legs.

Authorities do not think Whipkey was ever in the motel before her death, and investigators believe Mertz, who was living at the motel, killed Whipkey somewhere else and dumped her body there.

DNA testing exonerated Whipkey's former husband and a man she had been dating at the time of her death, authorities said.

Dalton said Mertz was identified as a suspect midway through the investigation.

Contact staff writer Allison Steele at 856-779-3838 or asteele@phillynews.com.