Federal officials are digging deeper into the life of the man who killed five service members in Tennessee, while officials in Jordan have been questioning the man’s relatives about his recent trip there.

On Monday night, the FBI visited an apartment to learn more about Mohammod Youssuf Abdulazeez. They were looking to interview a friend of Adbulazeez. Sources told CBS News the friend was cooperative and allowed agents into his residence.

A lawyer said one of Abdulazeez’s uncles in Jordan was in custody for several days after the attack under questioning.

Abdel Qader al-Khatib told The Associated Press on Tuesday that he was barred from seeing his client and that family members were prevented from visiting. Al-Khatib identified his client as Asaad Ibrahim Abdulazeez Haj Ali, a maternal uncle of the Tennessee attacker.

The Tennessee shooter had spent several months in Jordan last year, and a Jordanian government official said Tuesday that some of Abdulazeez’s relatives in Jordan were being questioned as part of an investigation into his stay in the kingdom.

Federal officials are still trying to determine why the 24-year-old fired approximately 100 rounds at two military sites last week. He had purchased ammunition at a Walmart while he was with two other men.

In 2013, he lost his job at a nuclear power plant for failing a drug test. A source close to the family says that soon after, Abdulazeez wrote about how far his life had fallen. He expressed suicidal thoughts, martyrdom, and anti-American sentiments — feelings he apparently wrote about again in the week leading up to the shooting.

Recently, law enforcement sources say Abdulazeez looked at the writings of radical cleric Anwar al-Awlaki, the American-born, Yemen-based cleric killed in a drone strike a few years ago, who was also known for inspiring Ft. Hood shooter Nidal Hasan.

But so far, the FBI has not turned up a direct link to al Qaeda, the Islamic State of Iraq and Syria, or any other terrorist groups overseas.

Federal investigators say there’s no evidence Abdulazeez met with extremists when he traveled to Jordan last year. A source close to the family also says relatives didn’t notice a negative change when he got back. They did try to get him to go to rehab to deal with his depression and drug issues but were unsuccessful.

Qatar says Abdulazeez transited through the Gulf state on his way back from a visit to Jordan but never set foot outside the airport.

Qatar’s government media office made the comments in a statement responding to questions from The Associated Press on Tuesday following news reports that Abdulazeez had visited the country.

The statement says Abdulazeez changed planes Doha’s Hamad International Airport on his way to the United States in November 2014.

It adds that statements suggesting “Abdulazeez entered the State of Qatar are false.”

Qatar has emerged as a major long-haul transit hub in the Middle East thanks to the rapid growth of government-backed Qatar Airways.