least 40 people stood at the crime scene tape stretched across the intersection of 59th and State streets late Tuesday, looking at the silver Dodge Charger in which a 26-year-old man had been shot to death.

Cass Singleton was driving south on State Street about 9:40 p.m. when people on the sidewalk and someone in a red sedan fired shots at him, police said.

He was shot in the head and died in the driver’s seat, his body slumped back as police investigated and the crowd gathered.

“59th Street going to be hot as a firecracker,” said a man in a Bulls cap.

Singleton belonged to a faction of the Black Disciples gang centered near 60th Street and King Drive, according to police and the Rev. Andre Smith, a local activist.

They’ve been feuding with nearby rivals lately, said Smith, who heard it was members of the rival gang who shot Singleton.

“The young people are saying it’s going to be war tomorrow,” he said. 

A small group surrounded a barefoot woman who had collapsed to the pavement near the crime scene tape just east of State Street. She was having difficulty breathing and sobbed loudly every few minutes. A family member identified her as the mother of Singleton's sister.

The crowd around her yelled at officers to get her help and they said they had called for an ambulance.

Suddenly the woman began having violent convulsions, arms and legs flailing, and the people around her jumped in to restrain her. After a few moments, she was still again, and rolled onto her stomach in the street.

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A thin woman in a sports bra walked up to nearby officers, demanding to know why they hadn’t helped and calling one a “f---ing dumba-- b---h.”

Three officers within earshot turned and walked toward the woman and her friends took her by the arm back into the crowd.

The woman on the pavement started convulsing again, shaking so hard she nearly sat up straight. Saliva covered her chin. An ambulance arrived moments later, and officers moved the crowd half a block east to make room.

Police allowed a woman with a small frame to stand just inside the police tape. She was quiet. No emotional display. People in the crowd spread word that she was Singleton's mother.

Jonai Nichols, 14, had tears in her eyes. She was Singleton's cousin, she said.

Singleton was the one who kept everyone out of trouble and helped make sure their grandmother’s house was spotless before she came home from work, Nichols said.

“That’s, like, my best friend, I could tell him all everything, all my secrets,” she said.

She said Singleton would put on music, like tracks by his friend 600 Breezy, then turn it up loud and try to goad Nichols into dancing with him: “Turn up! Turn up! Dance with me, cuz!”

Smith, who ran for alderman of the 20th Ward this year, said street violence causes psychological problems among young Chicagoans, many of whom show signs of post-traumatic stress disorder.

“There’s no way someone can kill someone stopped at the red light, 26 years old, (without having) a mental disorder,” he said. “It’s a sickness these young people have, killing each other.”

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