Frank Dillane has more to worry about right now than the zombie apocalypse.
The 25-year-old actor, who plays Nick Clark on AMC's Fear the Walking Dead, was arrested on a battery charge on Sunday, ET can confirm. Dillane was involved in a "physical altercation" with a security guard when he tried to enter the CBS lot in Los Angeles, California, according to the LAPD.
Dillane is being held on $20,000 bail and, as of Wednesday, LAPD confirmed he is still in jail.
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Dillane was "arrested by a private person" around 8:40 p.m. on Sunday evening and booked at 12:15 a.m. on Monday morning in the downtown Los Angeles jail.
As for what an arrest by a private person entails, an LAPD spokesperson explained, "This means when there is a misdemeanor committed not in law enforcement presence, after police arrive to investigate, a private person can say they want another individual arrested."
"Police then take that individual into custody and books them for the crime that was committed not in police presence," we're told. "On the flip side, when it's a felony crime, police are able to place someone under an arrest only with information as to what the incident was, they don't have to physically see it."
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Dillane previously appeared in the Netflix series, Sense8, and played a young Tom Riddle in Harry Potter and the Half-Blood Prince. On Fear the Walking Dead, he stars as the drug-addicted son of Kim Dickens' character. The show is currently in production, but, when reached, AMC had no comment.
When ET spoke with Dillane during a TCA press event before the premiere last year, he seemed nervous as he revealed the pressures of starring in the Walking Dead spin-off.
"I don't think it was fun at all, I think it was daunting because I had to sort of have like, the stakes were very high for me from the very beginning," he explained. "And that was like first episode, I was doing all kinds of weird s**t. So, it was daunting having to see the first zombie. It was like scary, 'cause, yeah."
Meanwhile, Walking Dead star Jeffrey Dean Morgan spoke with ET after season six's bone-chilling -- and, some might say, infuriating -- finale, jokingly revealing that he is going to "ruin" season seven. Hear more of what he said in the video below.