Portrait of the perpetrator of the bloody shooting in Orlando

Omar Mateen, the terrorist suspect in the attack on a gay nightclub in Orlando, was on the radar of the FBI more than once.

Omar Mateen, the perpetrator of the bloody shooting that killed at least 50 people (Source: Daily Beast)

The Daily Beast, citing anonymous police sources, said Mateen had been considered a target of federal security forces before he opened fire, killing at least 50 people in the deadliest mass shooting in US history. In total, Mateen shot more than 100 people.

Mateen, a native of Port Saint Lucie, Florida, has been designated a “person of interest” twice, first in 2013 and again in 2014. The FBI even considered opening an investigation into Mateen once, but ultimately decided against it.

Mateen, who was born in New York and married a woman living in New Jersey, told the Washington Post that Mateen beat her during their marriage, which lasted from April 2009 to July 2011.

“He was not a normal person,” she shared. “He beat me. He used to come home and beat me just because the clothes weren't done washing or something like that.”

She said Mateen's parents came to the United States from Afghanistan and he was not religious. She thought he was a nice, normal guy who became disillusioned after they got married.

Mateen's father, Mir Seddique Mateen, appeared on NBC News to speak about his son's horrific actions. "We want to apologize for this whole thing. We had no idea what he was planning. We were shocked like the rest of America," he said, adding that his son's attack had nothing to do with Islam.

But according to the Washington Post, Mir Seddique’s words may not be trustworthy, because he is a supporter of the Taliban in Afghanistan. He has long lived in Florida, but still runs an NGO in Afghanistan. He also believes that Pakistan’s Northwest Frontier Province should be returned to Afghanistan.

"Long live Afghanistan," Mir Seddique wrote on his Facebook page. "Death to Pakistan, death to you."

Two police officials told the Daily Mail that Mateen called 911 and pledged allegiance to the Islamic State (IS) group just before he began his rampage. In the San Bernadino shooting last year that left 14 people dead, the gunman also pledged allegiance to IS online.

The officers said there was no evidence Mateen had any direct ties to IS, but the group has recently called on Muslims around the world to attack Western targets during the fasting month of Ramadan, which began last week.

Amaq Agency, an IS-linked media outlet, praised the attack and claimed it was directed by IS. But there was no evidence of a link between Mateen and IS.

Several questions remain unanswered about Mateen. These include whether the private security company that employed Mateen, G4S, knew of his potential for serious crimes and whether they conducted a background check on him. Mateen had a gun permit as part of his job and had purchased a gun — the one used in the massacre.

Daniel Gilroy, who worked with Mateen at G4S, said he was a very "unstable" person who had talked about killing others. Gilroy reported Mateen's strange behavior to G4S, but no one took him seriously.

Such security flaws allowed Mateen to kill up to 50 people in the early morning of June 12 (US time), with an AR-15-style rifle. Mateen was later killed in a gunfight with SWAT forces.

It is known that the bloodiest massacre in American history by an individual occurred in Bath, Michigan in 1927, when a man bombed a school, killing 44 people. However, this "record" was broken by Mateen with his deadly shooting./.

According to VIETNAM+