Investigators say workplace video and other records helped reconstruct the hours before Carmen Lizet Puch was found dead near a Virginia trail.

GREAT FALLS, Va. — A restaurant surveillance camera, an early-morning phone call and evidence recovered in a gravel parking area helped Fairfax County investigators reconstruct the hours before 42-year-old Carmen Lizet Puch was found dead near Difficult Run Park, according to police and court-document reporting. Authorities charged her 19-year-old co-worker, Alexis Antonio Cedillos-Campos, with second-degree murder after locating him in Maryland two days later.

The investigation began shortly before 7 a.m. Aug. 17, when a person out for a morning run discovered Puch beside her 2011 Honda Civic in the parking area off Georgetown Pike. Fairfax County police said officers responding at 6:43 a.m. found Puch with injuries to her upper body and pronounced her dead at the scene. Investigators initially disclosed little about what had happened, but police said there was no immediate indication that the killing was random. Within roughly 48 hours, detectives publicly identified Cedillos-Campos as the suspect and announced that he had been arrested.

What police described later was a sequence they said began hours before Puch was discovered. Cedillos-Campos and Puch worked together at a restaurant in Herndon and had been involved in what Police Chief Kevin Davis described as an intimate relationship. Authorities said surveillance footage from the restaurant showed Cedillos-Campos leaving with a fixed-blade knife, black latex gloves and a water bottle. Davis said Cedillos-Campos emptied the bottle and put gasoline from his motorcycle into it before meeting Puch. The police account described those actions as evidence that the encounter was planned rather than spontaneous.

Later reporting on a Fairfax County criminal complaint added another layer to investigators’ timeline. A witness told detectives that Puch had sent screenshots concerning the relationship to Cedillos-Campos’ girlfriend, according to reports describing the complaint. The witness said Cedillos-Campos became upset, left work early and said he was going to kill Puch. That assertion is part of the prosecution’s developing account and has not been established at trial. Police initially said detectives were still examining the motive and the circumstances surrounding the relationship.

The same witness told investigators that a phone call around 1:30 a.m. appeared to arrange a meeting between Cedillos-Campos and Puch, according to the complaint as reported by local news organizations. Police said the two intentionally met at the Difficult Run parking area. Investigators believe Puch was attacked in or around her car. Davis said she was stabbed multiple times and gasoline was poured on her. He said the person who attacked her also tried unsuccessfully to ignite the gasoline. Authorities have described those details in restrained terms while continuing to investigate the sequence of events.

The physical evidence found at the scene helped support parts of the timeline described by the witness, according to reporting on the police documents. Investigators recovered black latex gloves and an empty water bottle that smelled of gasoline, and police documents said there was also an odor of gasoline on Puch. Workplace surveillance video was said to support the witness’s account that Cedillos-Campos had left the restaurant with a knife, gloves and bottle. Phone records also supported the existence of the early-morning call between Cedillos-Campos and Puch, according to the documents. A preliminary autopsy conducted Aug. 18 attributed Puch’s death to multiple sharp-force injuries and classified the death as a homicide.

The witness also told detectives that Cedillos-Campos called around 4 a.m. and said that he had done it before ending the call, according to reports on the complaint. The witness interpreted the statement as referring to Puch’s killing. That account is an allegation contained in the investigation, and the statement’s meaning and context ultimately would be matters for the court if the case proceeds to trial. Police separately said after Cedillos-Campos’ arrest that he was speaking with homicide detectives. Davis told reporters at the time that Cedillos-Campos was giving detectives what the chief characterized as a full confession about what had happened.

Detectives identified Cedillos-Campos during an investigation that included processing the parking area, reviewing surveillance footage and speaking with people connected to the restaurant where both he and Puch worked. Fairfax County police said their Fugitive Tracking and Apprehension Team coordinated with Prince George’s County police and the U.S. Marshals Service to locate him in Lanham, Maryland. He was taken into custody Aug. 19. Police announced that he faced a second-degree murder charge in Fairfax County. The charge is an accusation, and the allegations against Cedillos-Campos have not been proven in court.

The case developed rapidly after what began as an unexplained homicide in a small parking area serving trails near Great Falls. When police first spoke publicly on Aug. 17, they had not released Puch’s identity and were still determining when she had been killed. By Aug. 19, authorities said they had connected the victim to a co-worker, established that the two knew each other personally and assembled surveillance and other evidence they said showed preparations before the meeting. The later criminal-complaint reporting filled in additional allegations about what may have prompted the encounter, but those allegations remain subject to testing in court.

Puch lived in Reston. Police Chief Davis described her publicly as a loving mother of a young daughter. Victim specialists with the Fairfax County Police Department’s Major Crimes Bureau were assigned to assist her family after the killing, according to the department. Police have released few other personal details about her, while much of the public reporting has focused on the investigative timeline and the evidence authorities say links Cedillos-Campos to her death.

The second-degree murder case remains an allegation rather than a finding of guilt. Publicly reported evidence includes the workplace surveillance footage, witness statements, phone records and items police said were recovered near Puch’s vehicle. Authorities have not publicly established every detail of what occurred during the meeting at Difficult Run Park, and the witness account concerning the screenshots represents an alleged motive rather than an adjudicated fact. Any confession or other statements attributed to Cedillos-Campos also would be subject to the rules governing evidence in the criminal case.

As of the latest verified reporting reviewed for this story, Cedillos-Campos remained charged with second-degree murder in Puch’s death. No final determination of guilt has been made, and additional facts about the case may emerge through court filings and proceedings. Fairfax County police have continued to treat the Aug. 17 death as a homicide investigation while the criminal case moves through the judicial process.

Author note: Last updated September 28, 2026.