Buffalo supermarket shooting: Suspect was asked to leave store night before shooting

The man who shot and killed 10 people at a grocery store in Buffalo, New York, was asked to leave the store the evening before the shooting when he appeared to be bothering customers, a store manager said.

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Shonnell Harris Teague, an operations manager at Tops, the store where the shooting took place, told ABC News that she saw shooting suspect Payton Gendron sitting on a bench outside the store for several hours on Friday.

Gendron, 18, was dressed in camouflage, Teague said, and he had a bag on his back. He entered the store that evening, but he appeared to be bothering customers, so she asked him to leave, Teague said.

Gendron left Friday evening, but came back on Saturday and shot 13 people, killing 10.

Teague said she recognized Gendron as she was running from the store as the shooting began.

“I see him with his gear on and his gun and how it was all strapped on. … I (saw) all the other bodies on the ground,” she said. “It was just a nightmare.”

According to messages that Gendron had posted online, he apparently decided in December that he would stage an attack to kill those he called “replacers.” He decided in February to target Buffalo’s Tops grocery store, The Washington Post reported.

According to messages, he based his decision to target the Buffalo store because of its local African American community.

The messages posted revealed that he did a reconnaissance of the store in March where he made sketches and took photos of the grocery store.

A store guard confronted him after he repeatedly entered the Buffalo Tops store that day. Gendron said he made excuses and fled.

“I’ve seen you go in and out. … What are you doing?” the guard asked him, according to the online messages.

Gendron told the guard that he was “collecting consensus data” before making excuses and heading for his car, he wrote, adding: “In hindsight that was a close call.”