FORT PIERCE, Fla. — He was a body builder and a security guard, a religious man who attended the local mosque and who at one point expressed interest in becoming a police officer, though he never pursued it.

Early Sunday, 29-year-old Omar Mateen gunned down 50 people at a gay nightclub in Orlando, police said.

Mateen was the son of an Afghan immigrant who had a talk show in the United States, the nature of which was not entirely clear: A former Afghan official said the program was pro-Taliban and a former colleague said it was enthusiastically pro-American.

Mateen attended evening prayer services at the city’s Islamic Center three to four times a week, most recently with his young son, said Iman Syed Shafeeq Rahman. Although he was not very social, he also showed no signs of violence, Rahman said. He said he last saw Mateen on Friday.

“When he finished prayer he would just leave,” Rahman told The Associated Press. “He would not socialize with anybody. He would be quiet. He would be very peaceful.”

Mateen opened fire early Sunday at the Pulse nightclub, killing 50 people and wounding more than 50 others before he was gunned down during an exchange of fire with SWAT team members, authorities said. They say Mateen pledged allegiance to the Islamic State in a call to 911 on the morning of the shooting.

Rahman doesn’t think the attack was political or due to anti-American sentiment, though. He said it was more likely the result of psychological issues Mateen may have had.

“My personal opinion is that this has nothing to do with ISIS,” he said.

Seddique Mir Mateen, the father of the alleged shooter, is a life insurance salesman who started a group in 2010 called Durand Jirga, Inc., according to Qasim Tarin, a businessman from California who was a Durand Jirga board member. The name refers to the Durand line, the long disputed border between Afghanistan and Pakistan.

Tarin said Seddique Mir Mateen had a television show on which they discussed issues facing Afghanistan.

“It’s shocking,” he said about the shooting. “I don’t think it has anything to do with ISIS. (Omar Mateen’s) father loves this country.”

Some of Seddique Mir Mateen’s shows were taped and later posted on YouTube. During one episode, a sign in the background read: “Long live the U.S.A! Long live Afghanistan. … Afghans are the best friends to the U.S.A.”

But a former Afghan official said the “Durand Jirga Show” appears on Payam-e-Afghan, a California-based channel that supports ethnic solidarity with the Afghan Taliban, which are mostly Pashtun. Viewers from Pashtun communities in the United States regularly call in to the channel to espouse support for Pashtun domination of Afghanistan over the nation’s minorities, including Hazaras, Tajiks and Uzbeks, the official said.

The “Durand Jirga Show” expresses support for the Taliban, has an anti-Pakistan slant, complains about foreigners in Afghanistan and criticizes U.S. actions there, the official said. Seddique Mir Mateen lavished praise on current Afghan President Ashraf Ghani when he appeared on the show in January 2014, but he has since denounced the Ghani government, according to the official, who said that on Saturday, Seddique Mateen appeared on the show dressed in military fatigues and used his program to criticize the current Afghan government. He also announced on that show that he would run in the next Afghan presidential election, said the official, who spoke only on condition of anonymity because he did not want to be linked to coverage of the shooting.

Omar Mateen had no criminal record, but his ex-wife told The Washington Post that he beat her repeatedly while they were married. The woman, whom the Post did not identify, said she had met Omar Mateen online about eight years ago and decided to move to Florida and marry him. She said at first the marriage was normal, but then he became abusive, and the couple were only together for a few months. Records show that Mateen married Sitora Yusufiy of Port St. Lucie in 2009, but they were divorced two years later.

The ex-wife also said the Omar Mateen she knew was not very religious and gave no signs of radical Islam. She said he owned a small-caliber handgun. Mateen was a security guard at the G4S company, which identifies itself on its website as “the leading global integrated security company.”

Authorities immediately began investigating whether the assault was an act of terrorism. A law enforcement official said the gunman made a 911 call from the nightclub professing allegiance to the leader of the Islamic State, Abu Bakr al-Baghdadi. The law enforcement official is familiar with the investigation but was not authorized to discuss the matter publicly and spoke on condition of anonymity.

The shooter in 2013 made inflammatory comments to co-workers, and Mateen was interviewed twice, FBI agent Ronald Hopper said. He called those interviews inconclusive. In 2014, Hopper said, officials found that Mateen had ties to an American suicide bomber. He described the contact as minimal, saying it did not constitute a threat at the time.

Mateen purchased at least two firearms legally within the last week or so, according to Trevor Velinor of the Bureau of Alcohol, Tobacco and Firearms

Rahman said he knew Mateen and his family since the shooter was a young boy. Playful as a child, he became more serious as an adult, Rahman said. He spoke both English and Farsi, and at one point wanted to become a police officer but never pursued it, the iman said. He was also into body building. He was not, as far as the iman could see, someone who would ever commit such a gruesome act of mass violence.

The shooting “was totally unexpected,” Rahman said.