The FBI arrested 30-year-old Ahmad Suhad Ahmad in Tucson, Arizona, last week following a two-year investigation.

According to the limited information contained in the two-page criminal complaint, Ahmad had told a confidential source in December 2016 that he knew how to detonate a bomb using a cell phone — a technique he said he learned during the war in Iraq.

In April 2017, the same confidential source asked Ahmad if he knew how to make a car bomb for a target in Mexico, and if he could show him how to build one. Ahmad agreed.

A week later Ahmad showed the source an image on his cell phone of explosive materials and instructions written in Arabic, which he promised to translate into English. He also met with other sources and undercover FBI agents about planning to build the bomb.

On April 26, 2017, Ahmad traveled with the sources and the FBI undercover agents to an apartment complex in Las Vegas. He brought with him a number of items to build the bomb, including a circuit tester, electrical tape, and Permatex epoxy. The undercover agents also brought items from a list provided by Ahmad.

Over the course of several hours, he built the bomb and explained to the others how to do it. He showed one of the agents where to place the blasting caps and the explosives.

He then supervised the building of a second device. Once completed, he explained how the bombs operated.

Neighbors expressed surprise at his arrest:

Local media reports indicate that in November 2017, Ahmad, who operated a mechanic shop, was arrested for heroin possession and intent to distribute. He was released early as part of a drug-offender transition program on September 28.

Ahmad was born in Baghdad, Iraq, in 1988. His family fled to Syria when he was 18, and subsequently moved to Tucson as refugees. The FBI criminal complaint identifies Ahmad as a U.S. citizen.

This is the third arrest of an Iraqi refugee in a week.

As I reported earlier, 34-year-old Ashraf al-Safoo was arrested near Chicago and charged with running a pro-ISIS propaganda ring. According to the Justice Department, al-Safoo took orders directly from ISIS officials. Through social media, he spread propaganda on behalf of the terror group, helping ISIS to recruit and encouraging supporters to conduct terror attacks. He was born in Mosul, Iraq. and moved to the U.S. in 2008, and later became a naturalized U.S. citizen.

And last Wednesday, 19-year-old Naser Almadaoji of Beavercreek, Ohio, was arrested at Columbus International Airport attempting to fly to Kazakhstan, where he planned to cross the border into Afghanistan to join the ISIS affiliate there. The U.S. attorney responsible for the case said Almadaoji came to the U.S. from Iraq about a decade ago.

As noted by the 9/11 Commission Report, Tucson was the home of the first known American al-Qaeda cell, and is the former home of al-Qaeda co-founder Wael Julaidan — who was once the president of the Islamic Center of Tucson — as well as al-Qaeda operative Wadi al-Hage.

In March of this year, Syrian national and Phoenix-area resident Ahmed Alahmedalabdaloklah was convicted by a federal jury for designing, making, and supplying parts for remote-controlled IED initiator switches. They were for roadside bombs for an Iraqi terror group, and were responsible for killing American soldiers. Alahmedalabdaloklah had fled Iraq through Syria and China, and had settled in Arizona where the FBI found him after tracing his fingerprints at an IED factory in Iraq.

Tucson resident Mahin Khan was arrested in July 2016 for seeking weapons and bomb-making instructions from a Pakistani terror group.

Ahmad was arraigned in federal court in Tucson earlier this week, and is scheduled to appear back in court later today, where the FBI and Justice Department may provide more information about his case.