Investigators were reviewing a range of possible terror links to a gunman who opened fire at a crowded Orlando nightclub early Sunday, leaving at least 50 dead and 53 others wounded.

A federal law enforcement official identified the attacker as Omar Mateen of Port St. Lucie, Fla.

The official, who is not authorized to comment publicly, said Mateen, 29, is a U.S. citizen who was born in New York, and investigators were reviewing whether Mateen was known to law enforcement prior to Sunday's assault.

A second federal law enforcement official said Sunday that authorities were investigating the attacker’s possible utterances that may provide more specific information about a terror ideology or affiliation.

That official, who also is not authorized to comment publicly, characterized the attack as definitely terrorism.

Investigators were interviewing members of Mateen’s family Sunday in an attempt to learn what may have prompted the assault, the first official said.

NBC News reported that the attacker’s father indicated that Mateen recently expressed anti-gay sentiments, but the official said investigators were still reviewing a wide range of possible motivations.

The official also said investigators were reviewing Mateen’s recent travels and contacts to learn more about possible preparations for the attack, now the largest mass shooting in U.S. history.

As part of a wide-ranging investigation, federal authorities were tracing the origin of at least two weapons linked to the gunman, an AR-15 rifle and an handgun.

According to Florida court records, Mateen was married in 2009 and divorced two years later.

Mateen married Sitora Yusufiy on April 16, 2009. The marriage license was issued in St. Lucie County, Fla., records show. A dissolution of marriage was filed in July 2011.

Yusufiy could not be immediately reached.

Mateen attended Indian River State College in St. Lucie County during 2006 and 2007. Local law enforcement records show no apparent criminal history in Florida.

Contributing: Elliott Jones, Indian River (Fla.) Press Journal​

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