CHICAGO — Two people are dead after being shot inside a car on the city’s Southwest Side. A police officer is also hospitalized in connection with the shooting.

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According to police, the shooting occurred at the intersection of W. 21st Street and S. Western Avenue around 2 p.m. Two people – a 32-year-old man and a 29-year-old woman – were shot inside a vehicle traveling eastbound on W. 21st Street. An ambulance transported both victims to a nearby hospital in “extremely critical condition,” said fire officials, where they were later pronounced dead.

“I was at work and heard about eight shots. Immediately after, we thought they were fireworks,” said Paul Martinez, who was busy working in the area. “A white van peeled right through the light and took off…”

When police showed up at the crime scene, an argument broke out on the street, Martinez added.

“[After the shooting] I went to take out the trash. By then, there were a bunch of cops here. Maybe 15 minutes later, I heard a big commotion…through the alley and I just saw chaos,” he said.

A group of men became verbal with arriving officers. Amid the altercation, an officer was injured.

According to a Chicago police spokesperson, the CPD officer suffered a leg injury while trying to maintain control of the scene.

“They were tending to her leg for some kind of injury,” Martinez said. “The three guys, two of them were holding one back because he was trying to go at the officers.”

CPD personnel took three people into their custody as a result.

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Shortly after the fatal shooting, a lockdown at Mount Sinai Hospital went into effect. It is unclear if the lockdown was in connection with the deadly shooting.

Anyone with information about the shooting may leave an anonymous tip at cpdtip.com.