A witness told investigators that Carmen Lizet Puch sent screenshots of the relationship to the accused man’s girlfriend before her death.
GREAT FALLS, Va. — A witness told investigators that 19-year-old Alexis Antonio Cedillos-Campos threatened to kill co-worker Carmen Lizet Puch after learning she had sent screenshots documenting their relationship to his girlfriend, according to reporting on a Fairfax County criminal complaint that provides the clearest public account yet of an alleged motive in Puch’s Aug. 17 death.
The allegation significantly expands what police initially disclosed when Cedillos-Campos was arrested two days after Puch, 42, was found dead near Difficult Run Park. At the Aug. 19 arrest announcement, Fairfax County Police Chief Kevin Davis confirmed that the two restaurant workers had an intimate relationship but said investigators were still examining its circumstances. Police described evidence they believed showed advance preparation for the meeting but did not publicly attribute the killing to one specific dispute. The later complaint adds a witness account tying Cedillos-Campos’ alleged statements and actions to the disclosure of the relationship.
According to reports describing the complaint, the witness said Cedillos-Campos left work early after becoming upset about the screenshots and said he was going to kill Puch. The account has not been tested in court. It represents what a witness told investigators, not a judicial finding about motive or intent. That distinction is particularly important because prosecutors have charged Cedillos-Campos with second-degree murder, and the government will have to establish the elements of the charged offense through admissible evidence if the case reaches trial.
The witness also described conduct that police say is partly supported by surveillance footage. Authorities said video from the Herndon restaurant where Puch and Cedillos-Campos worked showed Cedillos-Campos leaving with a fixed-blade knife, black latex gloves and a water bottle. Davis said the bottle was emptied and then filled with gasoline from Cedillos-Campos’ motorcycle. Police characterized the sequence as preparation before the meeting with Puch. Later police-document reporting said surveillance footage supported the witness’s description of Cedillos-Campos leaving the workplace with those items.
The alleged planning continued through a telephone call, according to the complaint. The witness told detectives that at about 1:30 a.m. Aug. 17, Cedillos-Campos and Puch spoke by phone and arranged to meet. Police later said the two intentionally met at the Difficult Run parking area off Georgetown Pike in Great Falls. Call records corroborated the existence of the early-morning communication, according to reports on the documents. Those records may establish contact between the two phones, although the witness account provides the publicly reported description of what was discussed.
Authorities allege that Puch was attacked after arriving at the parking area. Police said she was stabbed multiple times and that gasoline was poured on her. Davis said there was an unsuccessful effort to ignite the gasoline. Investigators later reported finding black latex gloves and an empty water bottle that smelled of gasoline at the scene, while Puch also carried an odor of gasoline, according to the police-document reporting. The descriptions have been kept non-graphic because the essential evidentiary facts can be conveyed without unnecessary detail about her injuries.
The witness’s account contains another alleged statement after the attack. At around 4 a.m., Cedillos-Campos called the witness and said that he had done it before hanging up, according to reporting on the complaint. The witness interpreted the words as an admission that Puch had been killed. Authorities have not publicly released the full call or identified all of the circumstances surrounding it. If prosecutors seek to introduce the alleged statement, its precise wording, foundation and context could become issues in the criminal proceedings.
Several hours later, the case became a public homicide investigation. At 6:43 a.m., Fairfax County police were called to the parking area after a runner discovered Puch near her 2011 Honda Civic. Officers found her with upper-body trauma and pronounced her dead. Police initially did not release her name and said only that there was no immediate indication the killing had been random. An autopsy conducted the following day preliminarily attributed her death to multiple sharp-force injuries and classified the death as a homicide.
The investigation then moved rapidly across jurisdictional lines. Fairfax County detectives identified Cedillos-Campos and worked with authorities in Maryland to locate him. The Fairfax police department said its fugitive unit coordinated with Prince George’s County police and the U.S. Marshals Service, resulting in his arrest in Lanham on Aug. 19. Fairfax authorities announced the second-degree murder charge the same day. He was initially held in Maryland while authorities worked through the process of returning him to Virginia.
During the arrest announcement, Davis said Cedillos-Campos was speaking with Fairfax County homicide detectives and was providing what the chief described as a full confession. That police characterization is separate from the later witness account in the complaint. Public reporting has not established through a court ruling what statements Cedillos-Campos made, which portions prosecutors may seek to use or whether the defense will challenge them. A police announcement about a confession does not amount to a conviction.
The newer complaint reporting also illustrates how an alleged motive can emerge after an arrest without becoming a settled fact. Police first presented the case primarily through physical preparation and investigative evidence: video from the restaurant, the knife and gloves, the gasoline and the intentional meeting. The witness account later offered a possible explanation for why investigators believe that preparation occurred. The government still must establish that account with evidence, and the precise nature of the relationship among Puch, Cedillos-Campos and any third party has not been adjudicated.
Puch, a Reston resident, was a mother. Davis described her after the arrest as a loving mother of a 3-year-old daughter. Fairfax County police said victim-service specialists were assigned to help her family. Some secondary accounts have listed the daughter’s age differently, but the police chief’s description is the stronger official source. Cedillos-Campos was a co-worker rather than a stranger, according to investigators, and police have consistently said the park meeting was intentionally arranged.
The distinction between evidence of preparation and proof of legal guilt remains central as the case moves forward. Video footage may show what someone carried from a workplace. Call records may establish communication. Recovered objects may connect particular items to a scene. Witness testimony may describe statements allegedly made before and afterward. Prosecutors generally must bring those separate forms of proof together in court, where a defendant has the right to challenge their accuracy, meaning and admissibility. The public record reviewed for this story does not show that such a process has been completed.
Cedillos-Campos therefore remains accused, not convicted, of second-degree murder in Puch’s death. The complaint has added a potentially important allegation about motive, but it has not converted that allegation into an established fact. The criminal case will determine what can be proven about the meeting, the statements attributed to Cedillos-Campos and the events that ended with Puch’s death near Difficult Run Park.
Author note: Last updated September 28, 2026.