A man who ran naked across the George Washington Memorial Parkway after a bicyclist was strangled on federal parkland has pleaded guilty in the slaying along a popular bike and jogging path in Alexandria.

Andre D. Suggs entered his plea Tuesday in U.S. District Court in Alexandria, prosecutors said. He had been charged with felony murder in the May 28 death of Alexandria resident Mark Creasy, who was strangled on Daingerfield Island. Suggs later crossed the parkway naked and bit a police officer.

But Suggs pleaded guilty to second-degree murder, which drew criticism yesterday from the victim's sister. "I don't feel like the second-degree plea is what he deserves. I think he should have gotten first degree," Susan Creasy Brooks said in an interview. "He needs to go away for the longest of the long, because he is a menace."

Law enforcement officials said they understood Brooks's frustration. But prosecutors did not believe they could prove that the slaying was premeditated or that Suggs had intended to steal Creasy's bike, which would have been an essential element of felony murder. "Second degree seemed to fit what the facts were and was the way to accomplish justice in this case," said one law enforcement official, who spoke on condition of anonymity because the Justice Department is not speaking publicly about the plea.

Suggs faces up to life in prison when he is sentenced Feb. 10. Under the felony murder charge, he could have been eligible for the death penalty or would have received a mandatory life term. To prove felony murder, prosecutors would have had to show that Suggs killed Creasy while intentionally robbing him of his bike, officials said.

But officials said Suggs was disoriented during the slaying and might have grabbed Creasy's bike only to get away. Suggs hopped on the bike and briefly chased a witness, court documents said. The motive for the slaying remains unclear.

An attorney for Suggs, 36, of Alexandria did not return telephone calls yesterday.

The killing of Creasy, 48, was the second recent homicide on Daingerfield Island, a venue for biking, jogging, sailing, fishing and soccer. U.S. Park Police officials have said the area -- a 109-acre strip of land that extends into the Potomac River between Reagan National Airport and Old Town Alexandria -- is safe.

Creasy had been riding his bike along Marina Drive, a service road on the island, toward the Potomac River. Court documents said a witness on the riverbank heard several screams and went to investigate. The witness saw Suggs sprawled over Creasy's body, confronted Suggs and then rode off on his own bicycle to seek help.

Suggs followed the witness on Creasy's bike before fleeing into the woods, court documents said. Creasy's bike was found abandoned nearby.

Creasy loved riding his bike and would often cover 30 to 50 miles a day, his sister said. He especially loved riding near the parkway.

Less than an hour after the killing, Alexandria police arrested Suggs -- still naked -- about a half-mile away when he crossed the parkway at Bashford Lane. A park police affidavit said Suggs bit one of the arresting officers and screamed, "AIDS! AIDS! I got AIDS!"

Brooks, of Smyrna, Ga., said that she is "satisfied" with the Justice Department's handling of the case overall and that the plea did give her closure. "They got him off the streets," she said, "but it was at the expense of my brother's life.''