By MIKE BAKER

Associated Press Writer

FAYETTEVILLE, N.C. (AP) -- A pregnant soldier lay dead in the bathtub. Reportedly scrawled on the motel-room mirror in lipstick was a crosshair design — the same symbol contained in a letter that arrived at the local newspaper four days later.

"The following is to inform that I am responsible for the dead body," the typewritten letter read. "It was a master piece. I confess, that I have killed many times before in several states, but now I will start using my role-model's signature. There will be many more to come."

At the bottom was the same circle-and-cross drawing used a generation ago by San Francisco's infamous Zodiac Killer.

While police dismiss the notion there's a serial killer on the loose, the letter now appears to be an important piece of evidence in the investigation into the death last month of Army Spc. Megan Touma, a 23-year-old soldier at Fort Bragg.

Investigators are calling the case a homicide, but they say they have not established the cause of death and have offered no motive.

"We're pursuing every lead," said Chris Grey, a spokesman for the Army's Criminal Investigation Command. "We want to find out exactly what happened to Spc. Touma."

Authorities said they have identified a "person of interest" in the case, a soldier studying psychological warfare at Fort Bragg. Fayetteville police spokesman Lt. David Sportsman said the soldier is cooperating with investigators and has not been detained.

"We're not concerned about it," Sportsman said. "If the person flees, we'll go get 'em."

It was the second time in six months that a pregnant, unwed servicewoman in North Carolina was slain and a comrade fell under suspicion. In December, Lance Cpl. Maria Lauterbach, a 20-year-old clerk based at Camp Lejeune, was killed, and a fellow Marine was captured after fleeing to Mexico. Both victims were just weeks away from giving birth.

Detectives in the Touma case said the letter may, in fact, have come from the killer. The writing on the mirror was not public knowledge until The Fayetteville Observer published that detail over the weekend along with the contents of the letter. But investigators do not believe the author's claim to be a serial killer.

"We just believe that it was merely a tactic used to divert us off of what we are doing, and to cause panic in the community, which we have to deal with, too," Sportsman said. "But we don't believe there's a serial killer in Fayetteville."

Touma, who was from Cold Spring, Ky., was a dental specialist from a military family who joined the Army in 2003. Seven months pregnant, she had recently completed a three-year tour in Germany. She was last seen alive not long after she arrived on June 12 at Fort Bragg, home to the Army's 82nd Airborne Division and its Special Operations Command.

She was divorced. Authorities have said nothing about the father of her child.

Deb Skidmore, a spokeswoman at Fort Riley, Kan., has said Touma's family lives in Kansas but has declined to comment.

Her body was found by a maintenance man at an off-base motel on June 21. He entered the room, protected for four days by a "Do Not Disturb" sign, and noticed a foul odor. Among the items investigators removed were sections of drywall stained with what might be blood, according to court papers.

The Observer published the letter after holding back for three days at the request of Fayetteville police. The newspaper, citing unidentified sources, said the marking on the mirror inside Room 143 was made with lipstick and was identical to the symbol in the letter. Officially, police will say only that the symbols were similar.

The letter writer taunted Fayetteville law enforcement authorities as "very incompetent. I basically, sat there and watch while investigators were on site."

The Zodiac killer was blamed for at least five slayings in California in the late 1960s but never caught.

Fayetteville detectives and Army investigators were compiling evidence Tuesday and awaiting the results of a military autopsy on Touma. The details of an earlier autopsy done by civilian authorities have not been released.

"We're at a critical point right now," Sportsman said. "There's a lot of things going on right now. There's a lot of evidence being processed, a lot of interviews. It's just a matter of time."

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