BUFFALO, N.Y. (AP) — A white 18-year-old wearing military gear and livestreaming with a helmet camera opened fire with a rifle at a supermarket in Buffalo, killing 10 people and wounding three others Saturday in what authorities described as “racially motivated violent extremism.” Police said he shot 11 Black and two white victims before surrendering to authorities in a rampage he broadcast live on the streaming platform Twitch. Later, he appeared before a judge in a paper medical gown and was arraigned on a murder charge. “It is my sincere hope that this individual, this white supremacist who just perpetrated a hate crime on an innocent community, will spend the rest of his days behind bars. And heaven help him in the next world as well,” said Gov. Kathy Hochul, speaking near the scene of the attack. The massacre sent shockwaves through an unsettled nation gripped with racial tensions, gun violence and a spate of hate crimes. In the day prior to the shooting, Dallas police said they were investigating a series of shootings in Koreatown as hate crimes. The Buffalo attack came just one month after another mass shooting on a Brooklyn subway train wounded 10 people. The suspected gunman in Saturday’s attack on Tops Friendly Market was identified as Payton Gendron, of Conklin, New York, about 200 miles southeast of Buffalo.