OMAR MATEEN

The suspects in the shootings at a Uvalde, Texas, elementary school and a Buffalo, New York, supermarket were both just 18 when authorities say they bought the weapons used in the attacks.

The suspects in the shootings at a Uvalde, Texas, elementary school and a Buffalo, New York, supermarket were both just 18 when authorities say they bought the weapons used in the attacks.

The 49 people killed in a mass shooting at a gay nightclub in Florida have been honored in Orlando and around the world on the fifth anniversary of the attack.

These are the deadliest mass shootings in American history

A former acquaintance of Pulse nightclub shooter Omar Mateen says he tipped off the FBI when he became alarmed by Mateen's comments. David Begnaud reports.

After facing criticism, the FBI reversed its decision to release a partial transcript of Omar Mateen's call to police the night of the deadly attack and released the gunman's pledge to ISIS late Monday. CBS News justice reporter Paula Reid joins CBSN with the latest.

A partial transcript has been released of the Orlando gunman's calls to police the night of the deadly attack. Omar Mateen said he was the gunman and called himself an "Islamic soldier." CBS News homeland security correspondent Jeff Pegues joins CBSN with the latest details.

CBS News' Paula Reid discusses the 911 call transcripts released by the FBI. The transcripts detail phone calls made by Orlando gunman Omar Mateen in the midst of his deadly attack at Pulse nightclub.

CBS News' Jeff Pegues discusses the FBI's plans to release partial transcripts of 911 calls made by gunman Omar Mateen during his attack at the Pulse nightclub in Orlando.

Attorney General Loretta Lynch says Orlando nightclub killer Omar Mateen, did not mention the LGBT community in calls with a 9-11 dispatcher and hostage negotiator last Sunday. Lynch notes that the shooting took place on Latin night, raising FBI concerns over the attacker's motivation.

Investigators continue to look into Orlando gunman Omar Mateen's past and whether his wife played a role in the attack. Now a woman claims she was stalked by Mateen. CBS News has not been able to independently corroborate her story but has no reason to believe it's not true. There is at least one other woman who's come forward, telling The Associated Press she too was stalked by Mateen. David Begnaud has the details.

Newly released documents uncover the Orlando shooter's troubled past dating as far back as grade school. Reports of dangerous behavior and stalking are giving investigators a picture of Mateen's disturbing history. CBS News correspondent David Begnaud spoke with one woman who claims Mateen stalked her for years.

An official tells CBS News Orlando gunman Omar Mateen was active on dating sites, searching for both men and women. David Begnaud spoke with one woman who came forward, saying Mateen stalked her after meeting her at a courthouse. her after meeting her at a courthouse.

Law enforcement officials tell CBS News Omar Mateen was active on dating websites, and searched for both men and women. Also under investigation is Mateen's wife, who authorities say will likely face charges. Jeff Pegues has more.

Investigators know that Omar Mateen's wife was with him when he purchased ammo and they were communicating via text during the Orlando nightclub attack. CBS News' Jeff Pegues has the latest on the Orlando massacre investigation.

Sources tell CBS News that Noor Salman, the wife of the Orlando gunman, was communicating with Omar Mateen during the shootings. With evidence that he did some of the planning with her, Salman could face charges. We also know one of the gun stores Mateen visited before the attack tried to warn the FBI. Jeff Pegues reports.

New reports indicate Omar Mateen may have tried to buy armor and ammunition from a Florida gun store before the mass shooting and was turned away. The gun store owner says he called the FBI after becoming suspicious of Mateen. CBS News correspondent David Begnaud joins CBSn to discuss.

A gun shop owner says Orlando shooter Omar Mateen tried to buy body armor before the attack, but employees there were so concerned they called the FBI. That and other details emerged about events leading up to the deadly rampage in the Pulse nightclub.Jeff Pegues has more.

A gun shop owner says Orlando shooter Omar Mateen tried to buy body armor before the attack, but employees there were so concerned they called the FBI; President Obama has addressed the nation 14 times after mass shootings, most recently after the Pulse nightclub attack

CBS News' Jeff Pegues explains the FBI's previous inqiries involving Omar Mateen, and the next steps in the Orlando massacre investigation.

Investigators searched a home Monday belonging to the Orlando gunman's father. They also searched Omar Mateen's car just a few miles away. Family members and former friends are painting very different pictures of the gunman, whose persona largely remains a mystery. David Begnaud reports from Fort Pierce, Florida.

Luis Lopez was inside Pulse nightclub when gunman Omar Mateen opened fire and killed at least 50 people. Lopez made it out, but some of his friends did not. He's still waiting to hear if some of his friends are OK. Lopez spoke to the "CBS This Morning" co-hosts to discuss what he witnessed.

Former CIA deputy director and CBS News senior security contributor Michael Morell joins "CBS This Morning" from Washington to discuss the mass shooting that killed more than 50 people at an Orlando nightclub. Sources tell CBS News that gunman Omar Mateen called 911 and pledged allegiance to ISIS.

After the Orlando mass shooting, Donald Trump tweeted: "Is President Obama going to finally mention the words radical Islamic terrorism? If he doesn't he should immediately resign in disgrace!" More than 50 people died Sunday when Omar Mateen opened fire in an Orlando nightclub. The presumptive Republican presidential nominee joins "CBS This Morning" over the telephone to discuss the tragedy and what he thinks the country needs to do to respond.

The FBI spent the night combing through the Orlando shooter's home in Fort Pierce, Florida. Omar Mateen lived about two hours from the scene of the massacre at Pulse nightclub. Investigators also seized evidence from Mateen's father's home in Port St. Lucie, Florida. David Begnaud reports from outside Mateen's home in Fort Pierce.

A picture is emerging of the Orlando gunman, 29-year-old Omar Mateen, who was born in New York to Afghan parents. He had no apparent criminal record and was working as a security guard before the attack. Mateen was married for a second time and had a 3-year-old son. Jeff Pegues takes a closer look at his background, including some possible warning signs.

Childhood friend of the suspected Orlando mass shooting gunman is speaking out. CBSN's Josh Elliott sat down with the friend of Omar Mateen.

Speaking from her home in Boulder, Colorado, the ex-wife of Omar Mateen, the suspected gunman in the deadly Orlando mass shooting, said that Mateen wanted to be a police officer and had a license for a gun in Florida. Vladimir Duthiers and Elaine Quijano have more.

Former FBI assistant director Ron Hosko joins CBSN to discuss Omar Mateen's possible motive in the mass shooting at a gay nightclub in Orlando.

Authorities have identified the gunman behind the Orlando mass shooting at Omar Mateen. Former FBI profiler Dr. Mary Ellen O'toole joins CBSN with more on whether this could have been a planned attack.