CHAPEL HILL, N.C. — The North Carolina man accused of killing three Muslim students in a dispute over parking spaces had earlier run-ins with his neighbors, sometimes while wearing a handgun on his hip.

Police were still trying to determine whether religious hatred played any role in the shootings, which shocked the bucolic college town of Chapel Hill and left many residents grappling to make sense of the crime.

Charged with three counts of first-degree murder is Craig Stephen Hicks, 46, who has described himself as a “gun toting” atheist. Neighbors said Wednesday he always seemed angry and confrontational. His ex-wife said he was obsessed with the shooting-rampage movie “Falling Down,” and showed “no compassion at all” for other people.

His current wife, Karen Hicks, said her husband “champions the rights of others” and said the killings “had nothing do with religion or the victims’ faith.” She then issued another brief statement through her lawyer, saying she’s divorcing him.

Officers were summoned by a neighbor who called 911 Tuesday evening to report hearing multiple gunshots and people screaming.