Witnesses claim a Pennsylvania police officer became emotional and panicky after he shot 17-year-old Antwon Rose Jr.

Officer Michael Rosfield fatally shot the unarmed teen after he attempted to flee after a traffic stop, according to CBS News. An unlicensed taxi he was riding in was cited in a drive-by shooting. The gunman, Zaijuan Hester, shot at two men from the backseat as Rose sat in the front. Hester was forthcoming about his involvement and said Rose did not shoot anyone.

Rosfield was charged with criminal homicide, and his trial began on Tuesday, reports KDKA.

Resident John Leach testified he "couldn't believe his eyes" when he saw the shooting from his front porch. He said Rosfield was also in a state of disbelief.

Leach claimed Rosfield kept repeating, “I don’t know why I shot him. I don’t know why I fired. I don’t know why I shot” and appeared to be “panicking.”

Leach told the court Rose had at least one of his hands raised when he was shot.

“He put his right hand up close to his face,” Leach said. “I thought he was putting his hands up. He looked in both directions and then took off running.”

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Rosfield’s defense attorney accused Leach of giving a different account to police and said the view from his porch was obstructed.

“You didn’t say he put his hands up,” defense attorney Patrick Thomassey said. “You said he made a motion with his hand.”

Debra Jones, another neighbor, said Rosfield was emotional after the shooting. She said he began to fire as soon as Rose started to run. Jones said she did not see anything in Rose’s hands.

“Automatically,” she said. “Three shots. Boom, boom, boom.”

The trial is expected to last for more than a week. On the first day, Michelle Kenney, Rose’s mother, wrote a letter urging the prosecution to fight for her son’s honor.

“I know you have a strategy to obtain a conviction,” Kenney wrote. “I don’t know anything about trial strategy, but I know it is important that the jury has a chance to hear about who my son was. They deserve to know the real him. The defense has tried to make him out to be ‘just another thug,’ but please let the jury know who he really was.”

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Antwon Rose II

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