A federal judge in Los Angeles has declared a mistrial after jurors said they were unable to reach a verdict in the case of a Long Beach man accused of causing an explosion at an Orange County day spa in 2018 that killed his ex-girlfriend and injured two others.

Federal prosecutors on Monday said they will retry the case against Stephen Beal, with the case expected to return to court on Oct. 18.

Beal, a 63-year-old bit-part actor and model rocket hobbyist, was arrested at his East Long Beach home in 2019 in connection with a mass explosion at a spa in Aliso Viejo that killed his ex-girlfriend, Ildiko Krajnyak, 48, who was the spa owner, and seriously injured two of her clients.

In a federal trial that kicked off in June, Beal faced charges including using a weapon of mass destruction, malicious destruction of a building resulting in death and use of a destructive device in a crime of violence. Jurors deliberated for about seven days before informing U.S. District Judge Josephine L. Staton on Monday they were hopelessly deadlocked, according to news reports.

Krajnyak in May 2018 was inside her day spa business when she opened a cardboard box that erupted into a fiery explosion. The blast was so powerful that it blew out part of the building.

Shortly after the explosion, authorities searched Beal’s home and arrested him on suspicion of possessing explosives. Investigators said they found two improvised explosive devices, three firearms and more than 100 pounds of explosive material during the search. Beal later told authorities that the explosive devices were connected to his model rocket-building hobby.

In the trial, prosecutors said a jealous and obsessed Beal delivered a bomb to Krajnyak as revenge after she rejected him and dated other men, while the defense argued that Beal had no motive to kill Krajnyak and that the pair were “lovers, close friends and business partners.”

Prosecutors said Beal was seen on surveillance video purchasing the type of battery used in the explosive device about a week before the explosion. Prosecutors said Beal also allegedly purchased three cardboard boxes similar to the one that contained the bomb and was seen at the spa days before the blast, when they contend the bomb was planted.

The defense argued that while Beal had a history of “hobby rockets” and making fireworks, the material found in his home had no connection to the bomb.

City News Service contributed to this report.