Here in New York, a gunman wielding a semiautomatic assault rifle walked into a Midtown Manhattan skyscraper Monday evening and opened fire, killing four people before fatally turning the gun on himself. Police identified the shooter as 27-year-old Shane Tamura of Las Vegas, who reportedly drove across the U.S. to carry out the attack.

Jessica Tisch: “The building’s security camera footage shows the shooter enter the lobby, turn right and immediately open fire on an NYPD officer. He then shoots a woman who took cover behind a pillar, and proceeds through the lobby, spraying it with gunfire.”

Tamura was a competitive football player who appeared to be targeting the National Football League’s corporate offices. The league has confirmed one employee was critically injured. Tamura had a license to carry a concealed weapon in Nevada. He reportedly carried a suicide note stating grievances with the NFL and saying he suffered from the brain disease CTE, which is linked to head trauma.

Meanwhile, in Reno, Nevada, a gunman killed three people at a casino resort Monday morning, leaving several others injured in a spray of gunfire before police officers shot him dead. Investigators are still searching for a motive. According to the Gun Violence Archive, there have been 254 mass shootings across the U.S. so far this year.