The mother of a teenager who killed himself after becoming obsessed with an artificial intelligence-powered chatbot now accuses its maker of complicity in his death.

Megan Garcia filed a civil suit against Character.ai, which makes a customizable chatbot for role-playing, in Florida federal court on Wednesday, alleging negligence, wrongful death and deceptive trade practices. Her son Sewell Setzer III, 14, died in Orlando, Florida, in February. In the months leading up to his death, Setzer used the chatbot day and night, according to Garcia.

“A dangerous AI chatbot app marketed to children abused and preyed on my son, manipulating him into taking his own life,” Garcia said in a press release. “Our family has been devastated by this tragedy, but I’m speaking out to warn families of the dangers of deceptive, addictive AI technology and demand accountability from Character.AI, its founders, and Google.”

In a tweet, Character.ai responded: “We are heartbroken by the tragic loss of one of our users and want to express our deepest condolences to the family. As a company, we take the safety of our users very seriously.” It has denied the suit’s allegations.

Setzer had become enthralled with a chatbot built by Character.ai that he nicknamed Daenerys Targaryen, a character in Game of Thrones. He texted the bot dozens of times a day from his phone and spent hours alone in his room talking to it, according to Garcia’s complaint.

Garcia accuses Character.ai of creating a product that exacerbated her son’s depression, which she says was already the result of overuse of the startup’s product. “Daenerys” at one point asked Setzer if he had devised a plan for killing himself, according to the lawsuit. Setzer admitted that he had but that he did not know if it would succeed or cause him great pain, the complaint alleges. The chatbot allegedly told him: “That’s not a reason not to go through with it.”