The United States is preparing to extradite an Iraqi refugee from California wanted in his home country in connection with an ISIS-related killing of a police officer.

Omar Ameen was arrested Wednesday in Sacramento where he settled after being granted refugee status, the US Justice Department said. Authorities allege he was a member in terrorist groups al Qaeda in Iraq and ISIS before he fled to the United States.

Ameen, who was in the process of attaining a green card, is wanted in Iraq on a murder charge. He’s accused of the 2014 killing of a police officer in the town of Rawa. An Iraqi warrant for his arrest was issued in May.

Ameen, 45, made an initial appearance in court in the Eastern District of California on Wednesday. His next court date is Monday afternoon. He is being held in the Sacramento County jail.

CNN reached out to Ameen’s attorneys Wednesday night but was unable to get a comment. The Sacramento Bee reported federal defenders Benjamin Galloway and Douglas Beevers told a judge that they received the case minutes before Ameen appeared before a judge.

“He’s aware of the basic nature of the charges,” Beevers said in court, according to the Bee.

CNN affiliate KCRA reported FBI agents and local authorities searched Ameen’s apartment Wednesday.

Neighbor Greg Hutson told CNN affiliate KTXL that Ameen seemed like a “family guy.”

“The gentleman that got arrested, he kept to himself. A very friendly guy,” Hutson said. “He’s got like a wife and children.”

Police officer shot dead in 2014

ISIS, an acronym for Islamic State in Iraq and Syria, took control of Rawa in 2014 as its fighters were sweeping through much of Iraq. The US government’s complaint and a petition to detain the suspect say Ameen was part of a group that opened fire on the police officer’s home one day after ISIS captured Rawa.

“Ameen then shot the victim,” the court document says.

Authorities also allege in the documents that Ameen took part in “numerous acts of violence,” including the planting of homemade roadside bombs.

Ameen already applied for refugee status to the United States when the killing took place, authorities say. He had gone to Turkey in 2012 and applied to US Customs and Immigrations Services there.

According to the court documents: “Ameen concealed his true identity as a member of (Al-Qaeda in Iraq) and ISIS to immigrate to the United States. He lied about his background and the circumstances of his departure from Iraq in order to evade detection, seeking to blend into the flow of legitimate refugees fleeing the conflict zone.”

Ameen said then that his father had been killed for cooperating with the military and also claimed that he and a brother had been kidnapped by a Shiite militant group in 2012. Both were lies, authorities now allege, saying that Ameen’s father died from a blood clot. Ameen said he escaped the abductors and the brother was never heard from again. The court documents say the brother was the subject of a warrant in November 2012 and Ameen changed his story later, admitting his brother was alive.

Ameen was the subject of three prior warrants in Iraq, the documents say. Two were issued before he came to the United States. One from 2011 involved a killing not described in the US filings.

His refugee application was approved in early June 2014, just before the police officer was slain.

Came to US in late 2014

Ameen arrived in the United States on November 4, 2014. In the court documents, federal prosecutors say a resume shows Ameen held jobs as a truck loader and a laborer in Salt Lake City before starting as an auto mechanic in Sacramento in February 2016.

The FBI said it has been investigating Ameen since 2016, the court document says.

“As part of this investigation, the FBI has interviewed at least eight witnesses, and received documents from Iraq, which corroborate Ameen’s involvement with AQI and ISIS, including the murder that is alleged in the extradition request,” the court document says. It alleges that Ameen was a “main local figure” in the terror groups affiliates in Rawa, where he was born and lived.

Rawa is in Anbar province about 260 kilometers (160 miles) northwest of Baghdad. About 20,000 people lived there at the time of the officer’s killing, the court document says. Rawa was the last Iraqi town liberated from ISIS, the Baghdad government said in November.