A man accused of killing an Upper East Side deli worker while donned in a HAZMAT suit pleaded not guilty to first-degree murder Friday as chilling new details of the botched robbery emerged.
Kimond Cyrus, 39, calmly entered the plea in Manhattan Criminal Court after prosecutors detailed how he allegedly held a gun to a customer’s head before gunning down an elderly worker at Daona Gourmet Deli on East 81st Street and Third Avenue on March 3.
Cyrus allegedly pulled the shopper up from the floor and demanded cash from a clerk before fatally shooting 67-year-old worker Sueng Choi, said Assistant District Attorney Gregory SanGerman.
The unnamed customer told cops he broke free and then heard the sound of a gunshot as he ran from the store, according to a criminal complaint.

Cyrus allegedly pistol-whipped Choi with the gun when it went off, killing him, according to police. Cyrus was wanted for three other armed robberies at Big Apple delis and bodegas over a 10-day period.
At his Friday hearing, Cyrus looked straight ahead and remained silent except to enter his plea.

A judge remanded him without bail.
Meanwhile, neighbors mourned Choi’s violent death, remembering him as a hardworking Korean immigrant from Queens.
“He’s a nice guy. He never bother anybody,” said Choi’s landlord, who gave only his surname, Baek.

He said Choi was divorced from a Chicago woman, had recently lost his daughter and suffered a string of hardships.
“His daughter died last year of a heart attack,” Baek said. “His life is unhappy.”
Another neighbor, Juong Jhe Park, said he was baffled by why the robber had to kill Choi.
“Take [the] money,” Park said. “Why shoot?”