On April 27, 2011, Jeffrey Johnson confronted a coworker inside an elevator at their Midtown workplace and told him, "I am going to kill you," according to a police report.

It was not an empty threat. Friday morning, Johnson returned to Hazan Imports, the women's clothing company where he worked for six years until he was laid off last year, and shot and killed his coworker, Steven Ercolino, of New Jersey.

Johnson, 58, was apparently lying in wait for Ercolino outside the  company at 10 W. 33rd St., dressed in a gray suit, with a briefcase and a .45-caliber handgun.

He then shot Ercolino three times, once at close range, before attempting to flee.

Minutes later, Johnson was shot and killed by police, who were alerted by a construction worker who followed him down 33rd Street.

It was not clear what Johnson and Ercolino feuded about, but police said the two had filed harassment complaints against each other over the last year.

According to a LinkedIn page that has since been taken down, Johnson attended the Ringling College of Art and Design in Florida, and was the sole proprietor of a T-shirt company, St. Jolly T-shirt Art. 

A designer who has worked with both Johnson and Ercolino said that Johnson was fired from the company because he was doing too much work for his own business when he was supposed to be working for Hazan.

Law enforcement sources said Johnson blamed Ercolino for not pushing his line of products at Hazan enough, leading to poor sales. 

"I know there was animosity between them," said Nicholas D'Aurizio, who began working at Hazan after Johnson had left. "I know they had a not so great past. But nothing that would ever make you believe that something like this would happen."

After he was terminated from the company, Johnson periodically dropped by the Hazan offices to deal with paperwork involving COBRA health insurance, said a law enforcement source. He and Ercolino frequently argued at those times. 

Johnson had no criminal record. His handgun was purchased in Sarasota, Fla. in 1991, two law enforcement sources said. He was not licensed to carry in New York City. Johnson served in the Coast Guard from 1973 to 1977 and was honorably discharged as a 2nd class petty officer.

The superintendent of the Upper East Side building where Johnson lived described the man as a normal tenant who, for the most part, adhered to the same routine every day: wake up, go to McDonald's around 7 a.m. or 8 a.m. and return home. He also wore the same beige suit every day, the superintendent and neighbors said.

"We'd see him every morning all dressed up," said Gisela Casella, a 71-year-old crossing guard who used to let Johnson play with her dog Buddy. "He would dress up all the time like he was going to work, but he would always go to McDonald's." 

Casella described Johnson as fastidious and neatly dressed, and said he seemed to enjoy the company of animals more than people. She was shocked when she heard he was the gunman in the midtown shooting.

"I can't believe it," Casella said. "He was the nicest guy. I think he snapped or something."

Guillermo Suarez, the superintendent at Johnson's building, said Johnson had been living there for about 15 months. Suarez did not know whether he owned or rented his co-op unit, and rarely saw anyone else with Johnson except for when he first moved in, when he was with an elderly woman who appeared to be his mother.

Suarez said Johnson had the "same look" every single day he saw him. 

"Same suit," he said. "He always wear the same suit."

"He'd say 'good morning' and that was it," he said. "This morning, I saw him go. But he never came back. And then I get this call [from police]." 

Suarez said nothing seemed out of the ordinary when he saw Johnson. Later, when he went to let police into Johnson's apartment, he found the door unlocked.

Suarez said he was shocked when he heard the news that the man he had watched walk out the door an hour or so earlier was the man who had gunned down a former coworker in midtown.

Law enforcement officials said FBI, NYPD and ATF officers were at the suspect's apartment early Friday afternoon.

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