<b>UPDATE</b>

Louisiana state troopers on Friday arrested a 17-year-old girl and her 21-year-old boyfriend on suspicion of killing a Huntington Beach woman whose body was found floating in Newport Harbor on Wednesday.

According to Huntington Beach Police Capt. Dan Johnson, Louisiana troopers arrested the pair Friday afternoon while they were en route to Tampa Bay, Fla., in a black pick-up. Johnson identified the man as Ian Allen, 21, of Huntington Beach, but declined to give the girl’s name because she is a minor. The two are being held on suspicion of killing Barbara Anne Mullenix, 56.

On Wednesday afternoon, Mullenix’s body was found stabbed and floating, wrapped in a blanket, near the Newport Harbor Yacht Club. Mullenix, who was unemployed, lived in a Huntington Beach condominium with her ex-husband and 17-year-old daughter. The daughter was missing at the time Mullenix’s body was located, although Johnson would not say whether she was the girl arrested.

Mullenix’s body was found floating between a dock and a boat shortly after 4 p.m. on Wednesday. Johnson said Mullenix had been stabbed several times and that it was possible she had been dead for a while before her body went into the water.

After the arrest, Huntington Beach Police planned to send detectives to Louisiana to interview officers and to inspect the black pick-up. Detectives were busy examining several knives found in Mullenix’s condominium, at least one of which may have been used to kill Mullenix. Johnson said Mullenix’s ex-husband was out of town at the time of the killing and is not considered a suspect.Although some of Mullenix’s neighbors, according to Johnson, spoke of past conflicts between the mother and daughter, others described the household as tranquil.

Michael Harrison, an investment banker who lives in the complex, said he had seen the mother and daughter together a number of times and detected no tension between them. He described Mullenix as a quiet woman with an easy smile.

“She wasn’t overly talkative, but then most people here aren’t,” Harrison said.

Johnson said police tracked Allen and the 17-year-old after sources told them that Mullenix’s daughter had friends in Oklahoma City and Tampa Bay.

Police have responded to at least two dispute calls between the mother and daughter in the past, Johnson said.

Two Huntington Beach Police detectives were expected to fly to Lafayette, La., late Friday evening to process evidence and to interview the suspects.

Once charges are filed, Johnson said, Huntington Beach Police can request that Allen and the 17-year-old be extradited to Orange County.