The man accused of throwing a Molotov cocktail at the luxury home of OpenAI boss Sam Altman had written about artificial intelligence's purported risk to humanity and traveled from Texas to San Francisco intending to kill Altman, authorities said Monday.

Authorities allege 20-year-old Daniel Moreno-Gama threw the incendiary device at about 4 a.m. Friday, setting an exterior gate at Altman's home alight before fleeing on foot, police said. Less than an hour later, Moreno-Gama allegedly went to OpenAI's headquarters about 3 miles (5 kilometers) away and threatened to burn down the building.

Moreno-Gama is opposed to artificial intelligence, writing about AI's purported risk to humanity and "our impending extinction," according to a federal criminal complaint.

The Department of Justice (DOJ) said Moreno-Gama had traveled from his home in Texas to carry out the attack on Altman, whose company is behind the popular ChatGPT chatbot.

"Violence cannot be the norm for expressing disagreement, be it with politics or a technology or any other matter," said Acting Attorney General Todd Blanche.

"These alleged actions – which damaged property and could well have taken lives – will be aggressively prosecuted."

Prosecutors say that after lobbing a firebomb at the gates of Altman's home, Moreno-Gama fled on foot to the San Francisco headquarters of OpenAI, where he tried to smash the glass doors of the building with a chair.

The complaint says that when police arrived, they found Moreno-Gama with a jug of kerosene, a lighter and a document entitled "Your Last Warning," which "advocated against AI and for the killing and commission of other crimes against CEOs of AI companies and their investors."

Prosecutors say he ended the document, which included an admission he was trying to kill Altman, with the phrase: "If by some miracle you live, then I would take this as a sign from the divine to redeem yourself."

No one was injured in the home and office attacks, which came as Altman's profile has risen with the increasing use of AI. The CEO and his firm have become targets of protesters who view the technology as a threat to society.

Detractors have been particularly troubled by OpenAI's decision to provide its know-how to the U.S. Department of Defense.

"This was not spontaneous. This was planned, targeted and extremely serious," said FBI San Francisco Acting Special Agent in Charge Matt Cobo during a press conference.

Moreno-Gama faces charges, including two counts of attempted murder and attempted arson, in California state court, said San Francisco District Attorney Brooke Jenkins, according to an Associated Press (AP) report.

He tried to kill both Altman and a security guard at Altman's residence, she alleged. He is set to appear in court on Tuesday, and online state court records do not yet show if he has an attorney.

Jenkins said the state charges carry penalties ranging from 19 years to life in prison.

In a rare personal blog post, Altman defended his convictions and called for a de-escalation of rhetoric on the topic.

"I empathize with anti-technology sentiments and clearly technology isn't always good for everyone," he wrote.

"But overall, I believe technological progress can make the future unbelievably good, for your family and mine."

OpenAI last month said it was valued at $852 billion after a funding round that raised $122 billion.

The figure reflects the surging costs of computing power and came amid lingering questions about whether OpenAI and rival companies can generate sufficient revenue to cover expenses.

ChatGPT claims the top position in consumer AI, with more than 900 million weekly active users and some 50 million subscribers.

Use of ChatGPT's online search engine has tripled over the past year, according to OpenAI.