A Louisville bank employee armed with a rifle opened fire at his workplace Monday morning, killing five people - including a close friend of Kentucky’s governor - while livestreaming the attack on Instagram, authorities said, writes NBCCHICAGO.

Police arrived as shots were still being fired inside Old National Bank and killed the shooter in an exchange of gunfire, Louisville Metro Police Department Chief Jacquelyn Gwinn-Villaroel said. The city’s mayor, Craig Greenberg, called the attack “an evil act of targeted violence”.

The shooting, the 15th mass killing in the country this year, comes just two weeks after a former student killed three children and three adults at a Christian elementary school in Nashville, Tennessee, about 260 km to the south. That state’s governor and his wife also had friends killed in that shooting.

In Louisville, the chief identified the shooter as 25-year-old Connor Sturgeon, who she said was livestreaming during the attack. “That’s tragic to know that that incident was out there and captured”, she said.

Meta, the company that owns Facebook and Instagram, said in a statement that it had “quickly removed the livestream of this tragic incident this morning”.

Nine people, including two police officers, were treated for injuries from the shooting, University of Louisville Hospital spokeswoman Heather Fountaine said in an email. One of the officers, 26-year-old Nickolas Wilt, graduated from the police academy on March 31. He was in critical condition after being shot in the head and having surgery, the police chief said. At least three patients had been discharged.