Florida gunman Nikolas Cruz slurped on a cherry and blue raspberry Icee after slaughtering 17 people in one of the deadliest mass school shootings in U.S. history, a witness testified Thursday at his penalty trial. 

Cruz, 23, murdered 14 students, an athletic director, a coach and a teacher at Marjory Stoneman Douglas High School Feb. 14, 2018 – then fled the building, blending in with students who were evacuating. 

He went to a Subway inside a nearby Walmart and ordered the Icee, tossed coins into a tip jar then walked out, sandwich store manager Carlos Rugeles testified in Broward County Circuit Court.

Cruz pleaded guilty to 17 counts of first-degree murder in October. During the penalty trial, jurors will decide whether Cruz is sentenced to death or life without parole.

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Nikolas Cruz in court during jury selection

Marjory Stoneman Douglas High School shooter Nikolas Cruz tucks his sweater in while waiting for prospective jurors to enter the courtroom during jury selection in his penalty trial at the Broward County Courthouse in Fort Lauderdale, Florida, April 26, 2022.  (Amy Beth Bennett/South Florida Sun-Sentinel via AP, Pool)

Eight minutes later, Cruz entered a McDonald's, still drinking his Icee, and sat down in a booth across from Stoneman Douglas freshman John Wilford who did not know him, according to testimony and surveillance video played for jurors. There were several empty booths nearby.

Wilford told jurors that he had evacuated the school but hadn't yet learned it was due to a mass shooting. Wilford had just called his mom and arranged for her to pick him up at the McDonald's when Cruz slid into the bench across from him.

John Wilford chatted with Nikolas Cruz minutes after shooting

Former Marjory Stoneman Douglas High School student John Wilford testifies about encountering Nikolas Cruz at a McDonald's shortly after the Parkland school shooting.  (Mike Stocker/South Florida Sun Sentinel via AP)

He had been trying to reach his older sister Maddy, who he didn't yet know had been seriously injured by the stranger sitting across from him. 

"I didn't think much of it because I was panicked," Wilford testified of Cruz sitting next to him. "I was telling him, ‘This is so chaotic, this is crazy all these helicopters and squad cars coming. What do you think this could be?' I don't remember him saying much, but he was just, head down, wasn't really talking to me."

Surveillance footage of Nikolas Cruz after mass shooting

A screenshot of McDonald's surveillance footage showing then-Marjory Stoneman Douglas High School freshman John Wilford (right) chatting with Nikolas Cruz (on the left wearing a baseball cap) about 30 minutes after Cruz slaughtered 17 people. (Screenshot of trial evidence)

When Wilford's mom arrived, Cruz asked for a ride, but the student said no. 

"He was pretty insistent on it," Wilford told jurors. "I was just trying to get home, my sister wasn't answering her phone. I was nervous. I was panicked, and I also had a bad gut feeling about him."

Cruz walked away and was arrested about a half-hour later when an officer spotted him on a residential street. 

Wilford later learned that Cruz had shot his sister, Maddy. Three bullets ripped through her abdomen and pierced her right lung. A fourth tore into her arm. She survived.

The Associated Press contributed to this report