TAMPA — A former neo-Nazi and self-professed Muslim accused of shooting to death two of his roommates is not mentally competent to stand trial, a doctor has found.But prosecutors want a second opinion before a judge decides what to do with Devon Arthurs, who faces two counts of first-degree murder.In a brief court hearing Thursday, Assistant State Attorney Ronald Gale said the prosecution was not ready to accept the findings of Dr. Yolanda Leon, whose examination found that Arthurs is incompetent."It appears to me in some areas of the report that the defendant exhibited an understanding of some of the issues in question," Gale said.Over the objection of Arthurs’ defense, Hillsborough Circuit Judge Laura Ward granted the state’s request to appoint a second expert, ordering Dr. Daniel Patz, a psychologist, to examine Arthurs.The matter will be revisited at the next court hearing, set for Feb. 28.RELATED:Suspect in neo-Nazi murders tells of anger problem, says ‘I might be kind of sick’Prosecutors say Arthurs, 18, used an assault rifle to kill Jeremy Himmelman, 22, and Andrew Oneschuk, 18, inside the Tampa Palms condominium they shared with a fourth man. After the murders, Arthurs walked to a nearby smoke shop and held three people at gunpoint before officers arrived and persuaded him to surrender, police said.In an interview with detectives, Arthurs said he and his roommates had been neo-Nazis. until he converted to Islam. He said he killed them because they showed disrespect toward his new faith.During an investigation of the crimes, police found explosive chemicals and other bomb-making materials in a garage adjacent to the condo. The items belonged to the fourth roommate, Brandon Russell, who was not home at the time of the murders.Russell later pleaded guilty to federal charges related to the explosives and was sentenced to five years in prison.Arthurs was not in court for Thursday’s hearing.