Deshawn Thomas, man shoots homeless man
© TwitterA bystander taking video caught the murder happening in broad daylight.
A St. Louis man was arrested Tuesday after a video appeared to catch him nonchalantly shooting a homeless man execution-style in broad daylight.

Deshawn Thomas, 23, was arrested in connection with the Monday murder but has yet to be charged, police said.

Thomas can be seen struggling to load his gun as he stands right behind the homeless man, who is sitting on the curb just a few feet away, a bystander video posted online shows.

He then appears to fire at the yet-to-be-identified victim, who raised his arms at one point, but made no attempt to run away and seemed almost resigned to his fate, the video shows.

"Oh my God. He just f-king killed him," the witness can be heard saying.

The shooting happened in the heart of downtown St. Louis around 10 a.m. Monday, police said.

"Any homicide is unnerving," Major Ryan Cousins told the St. Louis Dispatch at the scene, "but for this one to happen here, at this time, very much so."

The victim, whose name has not been released, had fended off Thomas at a Shell gas station just minutes before. Thomas chased him across the street before allegedly shooting him, police said.

Cousins said the victim was likely in his 40s but didn't provide more details about him.

The video was posted on Twitter but was taken down due to its graphic nature.

"Twitter took down this video I posted yesterday so I'll post it again," the person who posted the video wrote, according to the Riverfront Times. "Doesn't show the murder on camera so stop censoring it."

Thomas was taken into custody by police at a local library after fleeing.

US Sen. Josh Hawley (R-Mo.) retweeted the video on Tuesday and called for St. Louis' embattled circuit attorney to resign.

"Kim Gardner must go. Prosecute the criminals," the Republican lawmaker wrote.

Deshawn Thomas
© St. Louis Police DepartmentDeshawn Thomas, 23, was arrested at a library after fleeing the scene of the shooting.
Before the video of the Monday murder surfaced, Gardner was already under fire after a driver facing felony charges for robbery โ€” who had violated his bail conditions multiple times โ€” hit a teenager earlier this month, causing her to lose her legs.

Missouri Republicans have called for the state to handle the prosecution of violent crimes instead of Gardner, and filed court documents recently in an attempt to fire her.