UNITED STATES—Omar Mateen, 29, went to the gay nightclub Pulse in Orlando, Florida on Sunday, June 12., armed with an assault rifle and a pistol as he shot and killed 49 people and injured 53 people leading to the deadliest mass shooting in U.S. history. More details about Mateen and the investigation have come to light in the days since the attack.

Mateen’s wife, Noor Z. Salman, 30, claims to have known about Mateen’s plan to attack. Salman married Mateen in 2011 and is Mateen’s second wife. His first wife, Sitora Yusifiy, who he was married to in 2009, said that Mateen had beat her.

Investigators are trying to corroborate Salman’s story to find out if she was also abused by Mateen. What the investigation into Salman has uncovered is that Salman accompanied him to buy ammunition that was used in the Pulse shooting. She also went with Mateen to Pulse once before his attack to do surveillance. She also accompanied him to do surveillance at Disney World on April 26, according to CNN. She claims to have told Mateen not to commit the attack on Pulse as he left for Orlando on Saturday night. Salman is not under arrest, but could potentially face charges as an accessory to murder.

After the shootings the suspect’s father Seddique Mateen released a statement about his son’s actions. He said that his son had come to visit him the day before the shooting at his home in Port St. Lucie, Florida and showed no signs of anger or anxiety.

“I apologize for what my son did…We are saying we are apologizing for the whole incident. We weren’t aware of any action he is taking. We are in shock like the whole country,” Seddique said in an interview with NBC News.

Seddique also said that this had nothing to do with religion, according to USA Today. He noted that Mateen had recently expressed anti-gay sentiments when he saw two men kissing in Miami a couple months prior to the attack.

Investigators are also looking into possible use of gay chat rooms and dating apps by Mateen prior to the attack. According to reports, Mateen had also frequented Pulse for years before the attack. Chris Callen, a performer at Pulse, said Mateen had visited Pulse about twice a month for three years.

According to CNN, Callen said, “He was very friendly when we said, ‘Hi.’ He didn’t seem like the kind of guy who just did what he did. It makes no sense. My partner said that he was very nice (and seemed) comfortable.”

Mateen’s former colleague, Dan Gilroy, said that Mateen had a temper. “He was an angry person, violent in nature, and a bigot to almost every class of person,” said Gilroy to CNN.

The investigation is ongoing. Canyon News called the FBI’s Main National Press Office to gather more information on the investigation, but was unable to receive comment before publication.

The names of the 49 victims from the Orlando shooting have been released and are listed below:

Stanley Almodovar III, 23; Amanda Alvear, 25; Oscar A Aracena-Montero, 26; Rodolfo Ayala-Ayala, 33; Antonio Davon Brown, 29; Darryl Roman Burt II, 29; Angel L. Candelario-Padro, 28; Juan Chevez-Martinez, 25; Luis Daniel Conde, 39;  Cory James Connell, 21; Tevin Eugene Crosby, 25;  Deonka Deidra Drayton, 32; Simon Adrian Carrillo Fernandez, 31; Leroy Valentin Fernandez, 25;  Mercedez Marisol Flores, 26;  Peter O. Gonzalez-Cruz, 22;  Juan Ramon Guerrero, 22; Paul Terrell Henry, 41; Frank Hernandez, 27; Miguel Angel Honorato, 30; Javier Jorge-Reyes, 40; Jason Benjamin Josaphat, 19; Eddie Jamoldroy Justice, 30;  Anthony Luis Laureanodisla, 25;  Christopher Andrew Leinonen, 32; Alejandro Barrios Martinez, 21;

Brenda Lee Marquez McCool, 49; Gilberto Ramon Silva Menendez, 25; Kimberly Morris, 37; Akyra Monet Murray, 18; Luis Omar Ocasio-Capo, 20; Geraldo A. Ortiz-Jimenez, 25; Eric Ivan Ortiz-Rivera, 36; Joel Rayon Paniagua, 32; Jean Carlos Mendez Perez, 35; Enrique L. Rios, Jr., 25; Jean C. Nives Rodriguez, 27; Xavier Emmanuel Serrano Rosado, 35; Christopher Joseph Sanfeliz, 24; Yilmary Rodriguez Solivan, 24;  Edward Sotomayor Jr., 34; Shane Evan Tomlinson, 33;  Martin Benitez Torres, 33; Jonathan Antonio Camuy Vega, 24 Juan P. Rivera Velazquez, 37; Luis S. Vielma, 22; Franky Jimmy Dejesus Velazquez, 50; Luis Daniel Wilson-Leon, 37 and Jerald Arthur Wright, 31.