Authorities said the same man later threatened to burn OpenAI’s San Francisco headquarters.
SAN FRANCISCO, CA — San Francisco police arrested a 20-year-old man after authorities said he threw an incendiary device at the home of OpenAI CEO Sam Altman before dawn Friday, setting fire to an exterior gate and later making threats at the company’s headquarters across the city.
No one was injured, but the episode quickly drew national attention because it targeted one of the country’s most visible artificial intelligence executives at a time of growing tension around the technology and the company behind ChatGPT. Police said the suspect was taken into custody less than an hour after the fire was reported. OpenAI confirmed that the house belonged to Altman and said it was cooperating with investigators as authorities worked to determine a motive and whether additional charges would follow.
Police said officers were called at about 4:12 a.m. Friday to investigate a fire at a San Francisco residence in the Russian Hill area. When officers arrived, they found that a man had thrown what police described as an incendiary destructive device at the property, causing a fire at the gate before running away on foot. The fire was put out quickly, and no one inside the home was reported hurt. OpenAI later said the targeted home belonged to Altman. “Thankfully, no one was hurt,” the company said in a statement released later Friday, adding that it appreciated how quickly the San Francisco Police Department responded. The company also said the suspect later made threats against its offices and that employees were safe. By late Friday, police had not announced a motive. By Sunday, several local reports, citing court and jail records, identified the suspect as Daniel Alejandro Moreno-Gama, 20.
According to police, the case widened within minutes of the first call. About an hour after the residential fire, officers responded to the 1400 block of Third Street in Mission Bay, where a man was reported to be threatening to burn down a building. That address is home to OpenAI’s San Francisco headquarters. Officers recognized the man as the same person sought in the earlier fire investigation and detained him at the scene, police said. Authorities have said the suspect remained in custody while the investigation continued. Local reports on Sunday said he had been booked on allegations that could include attempted murder, arson, criminal threats and destructive-device counts, though authorities had not publicly laid out a full narrative of intent. Police statements released Friday were more limited, saying only that the man was arrested in connection with the fire and later threats. Investigators did not report injuries at either location, and officials did not say whether anyone had to be evacuated from the office building.
The attack landed at a moment when OpenAI and Altman are under unusually sharp scrutiny. Altman has become one of the public faces of the fast-moving AI boom, and OpenAI has drawn praise, fear and protest as its tools spread through schools, offices and government agencies. The company has also faced criticism over safety, secrecy, labor issues and the social effects of powerful AI systems. In a post after the attack, Altman suggested that public rhetoric around AI had grown more heated than he previously understood. He wrote that he had “underestimated the power of words and narratives,” reflecting on how debates over the technology can spill beyond conference stages and policy papers. He did not accuse any individual or group of directing the attack, and police have not publicly tied the suspect to a broader organization. That leaves a central question unresolved: whether the incident was driven by a personal grievance, anti-AI activism, mental health issues, or some combination that investigators have not yet explained.
Public records and police procedure now shape what comes next. When a suspect is arrested in San Francisco on serious felony allegations, police typically present the case to prosecutors, who decide which charges to file and when the defendant will first appear in court. As of the weekend, authorities had said the investigation was active, and they had asked anyone with information, video or other evidence to contact police. That suggests detectives are still trying to establish a fuller timeline, including where the suspect went after the device was thrown, whether the device was assembled locally, and whether there were any prior threats directed at Altman or OpenAI. Officials also have not publicly said whether surveillance footage from the home, the street or the company’s offices captured the suspect’s movements from the first scene to the second. Any formal complaint, arraignment date or court hearing would likely provide the first detailed account under oath of how prosecutors believe the events unfolded.
By Friday evening, the visible damage appeared to be limited to the exterior gate, but the symbolism of the attack was larger than the physical harm. A predawn fire at the home of a tech executive who has come to represent both the promise and the fear of artificial intelligence quickly became a flashpoint in San Francisco, where debates over technology often blur into arguments about power, wealth and public safety. Neighbors in the hilltop area woke to police activity and fire investigators, while employees at OpenAI learned that the same suspect was accused of making threats outside their workplace. OpenAI said it was helping law enforcement and focused on worker safety. Altman, writing after the incident, struck a personal note about his family and the shock of seeing political and technological anger come so close to home. Even with an arrest made quickly, the broader meaning of the case remains unsettled until investigators say more.
As of Sunday, the suspect was in custody, no injuries had been reported, and investigators had not publicly announced a final motive. The next milestone is expected to come in court filings or a prosecutor’s charging decision that could spell out the allegations in detail.
Author note: Last updated April 12, 2026.