Texas Terror News 2015: One of 2 Slain Gunmen Who Attacked Texas Mohammad Art Show Had F.B.I. Terror Record

One of the two slain gunmen behind the shooting at a "Draw Mohammad" contest and exhibition in Texas reportedly had been the subject of an F.B.I. probe nine years ago for allegedly planning a terrorist attack in the U.S.

The other gunmen, on the other hand, was reported to have had a happy childhood in Pakistan before moving with his mother to the U.S. where he faced difficulty in adjusting to his new environment.

Elton Simpson, 30, from Phoenix, Arizona, was investigated by F.B.I. agents back in 2006. Agents even hired an informant at the mosque he often visited to find out if he was engaged in a terrorist plot, the New York Post wrote on Monday.

Simpson wanted to go to Somalia, through South Africa, to join Islamic militants, the Post report said.

"If you get shot, or you get killed, it's [heaven] straight away".... "[Heaven] that's what we're here for...so why not take that route?"' he allegedly told the informant.

He was convicted in 2011 for lying to the F.B.I. about his plans to travel to Africa. The judge, however, ruled that the government did not have sufficient proof that Simpson was going to join a terror group there. He was then given a three-year probation sentence.

His father, Dunston, said his American-born son, an Islam convert who had been working in a dentist's office and liked basketball, "made a bad choice."

"We are Americans and we believe in America," he told ABC News on Monday.

Usama Shami, president of the Islamic Community Center, a mosque three miles away from where Simpson and Soofi lived, said Simpson was well-liked by the young men of the mosque, The New York Times reported.

Turning to Islam while in high school, he adopted the Muslim name Ibrahim but never engaged in radical speech at the mosque. He focused on basic issues about his faith, asking questions about fasting, courtship, and marriage.

But after his federal case, Simpson seemed a changed man.

"There were no flashes of anger or radicalization, just an absence of happiness," said Shami, who noted that Simpson would only occasionally show up on Fridays.

The F.B.I. and the police again opened another investigation into Simpson months ago after he started posting online about the Islamic State.

Authorities believe Simpson posted terrorism-related tweets before the shooting incident, including one with the hashtag #Texasattack sent half an hour before he and another gunman, 34-year-old Nadir Soofi, tried to shoot their way into a politically charged art show. Any depiction of Prophet Muhammad is banned in Islam.

While Simpson was already a familiar name to the F.B.I., Soofi was not part of any previous investigation.

Soofi was described as a quiet man who ran a carpet-cleaning business in Phoenix. He often prayed at the mosque near Simpson's apartment and was sometimes joined by his son.

Soofi once owned a pizza and hot-wings restaurant called Cleopatra. He was said to have drifted away from the mosque while running it.

According to the Facebook page that appears to be Soofi's, he graduated from the International School of Islamabad in Pakistan in 1998 and attended the University of Utah. His first cousin, however, said Soofi was born in the U.S.

Soofi's friends at the said international school in Pakistan were shocked to learn that police identified him as one of the attackers.

"When he was in Islamabad, he had a great life. His mom was an American who taught art at the school. He was in plays, popular with girls," said one of Soofi's best friends at school. Soofi's nickname was "Goofy" because of his humor.

Another classmate said Soofi played the lead role in the school production of "Bye Bye Birdie."

"He was a popular kid, the opposite of a radical extremist," she said.

Soofi moved to Utah with his mother when his parents divorced during his tenth grade.

Soofi told his old friends over the years that he did not fit in and had many disappointments.

He had to drop out of dental school because of financial problems. He had a child with a Bosnian woman whose relationship with him did not work out.

"He said 'life is really tough here,'" the male friend said. "Alienation, an identity crisis, whatever you want to call it, he was kind of alone."

"I guess the one thing he could identify with was religion."

Soofi grew a beard and only posted pictures of himself wearing sunglasses on Facebook. His old friends teased him for that but they also started to worry. They gradually lost contact.

"I looked at his pictures, and I didn't recognize him," a friend said. "I don't know what happened to him in America."

Soofi moved to Arizona from Texas some years ago and he and Simpson became friends. Shami said nothing seemed out of the ordinary.

On Sunday night, Simpson and his roommate Soofi tried to attack the Muhammad cartoon contest at the Curtis Culwell Center in Garland, Texas.

A statement by the ISIS read over the Al Bayan radio on Tuesday said that "two of the soldiers of the caliphate" executed the attack in Garland, Texas.

"We tell America that what is coming will be even bigger and more bitter, and that you will see the soldiers of ISIS do terrible things," the group warned.

This marked the first time that ISIS owned responsibility over an attack in U.S. territory.