The case of a Chinese food delivery man who was missing for almost four days inside Tracey Towers, only to turn up unscathed in a stuck elevator, has police and local residents scratching their heads.

Ming Kuang Chen, who has been in this country for two years, went to Tracey Towers to make three deliveries, the last to an off-duty police officer. But an hour or so later, when he didn’t return, his co-workers called the police who found Chen’s delivery bike still outside the building.

A three-day search of Tracey’s 871 units ensued. A large mobile command unit truck took up residence on Mosholu Parkway South and over 80 officers pulled from precincts all over the borough conducted the search. Helicopters searched from above and dogs trained to search for cadavers were also on the scene. Police even scoured the Jerome Park Reservoir and the nearby subway yards.

Chen, 35, was out on a delivery from Happy Dragon, a Chinese takeout restaurant on Jerome Avenue, just a couple of blocks from Tracey. He works the-re six days a week, 12 hours a day to support his wife and son back in southeastern China.

The story received citywide attention as many feared that Chen might have met the same grim fate as two other deliverymen who were murdered by teenagers in recent years.

On Sunday, two days after Chen disappeared, Councilman John Liu of Queens, the first Chinese-American elected to the City Council, collaborated on a press conference at Tracey with Councilman Oliver Koppell. Joined by Chen’s co-workers, they asked that anyone in the community with information, provide it to police.

Two days passed, when finally, early Tuesday morning, the Fire Department was called to inspect a stuck elevator in the building after an alarm sounded around 5 a.m. When they got the doors open, they discovered Chen inside — standing, according to some accounts.

He was taken to Montefiore Medical Center and doctors there pronounced him in good health.

Dr. Babak Toosi, of Montefiore’s Emergency Department, said there were no signs of trauma on Chen’s body and that while he was dehydrated, he never passed out.

“He is young and his body can tolerate loss of water to a certain extent,” Toosi said.

A police source said that Chen said he had hit the alarm and intercom button in the elevator several times before Tuesday morning.

No one could explain how the stuck elevator — there are six in each of Tracey’s two buildings — could have gone unnoticed for so long, particularly by police who were scouring the building and Tracey’s own security detail. Paul Browne, deputy commissioner for public information at the NYPD, said in a telephone interview that the police were particularly perplexed that security monitors with views of the interior of the elevators did not reveal that Chen was inside during the course of the search.

“That’s not to say Mr. Chen wasn’t telling the truth,” Browne said, pointing out that it was possible for them to have missed Chen if he was crouching in one particular corner the entire time. “It would just have to be extremely bad timing all the time by three different entities [the police, Tracey security, and elevator maintenance staff] who would all have to miss him at different points throughout those days.”

RY Management, the company that runs Tracey, did not return a call for comment by press time.

But elevator problems, and structural problems in general, at Tracey are not new. The Norwood News reported just over a year ago that one of the tenants’ main gripes is the condition of the elevators.

“You have to pray every time you get in the elevator not to get caught,” said tenant Gerry Powell at the time. Many of the floor indicators didn’t function as well.

Though Chen was found alive and well, and officials praised the police while the search was under way, questions are being raised about another aspect of the Police Department’s performance.

At press time on Tuesday, Liu issued a press release praising the police for the “vigor with which the Department searched for Chen,” but he also charged that the Department violated mayoral Executive Order 41. That order directs city employees “not to take it upon themselves to enforce federal law,” Liu said, referring to some press reports quoting police stating that Chen was an illegal immigrant who had been smuggled into the country.

“The issue is that some police officers apparently made a statement that he was an undocumented immigrant. Executive Order 41 explicitly says that you don’t do that. That’s it,” Liu said in a telephone interview. “Now, [this] places Ming in jeopardy, but more importantly we’ve been undertaking a lot of efforts to get the new immigrant community to cooperate more with the police and to seek help from the police when they need it. What’s happened here is just going to turn back those efforts.”

But police officials disagreed with Liu’s assessment of the situation. “My response to that is that news media exploitation of its own sources does not equate to notification of federal authorities by the NYPD,” Browne said.

He also said he was “confident that no one in that investigation in an official capacity” [provided the information about Mr. Chen’s immigration status to reporters]. But he added, “That doesn’t mean it didn’t leak” from another source.

Browne said that the Police Department “is an advocate of Executive Order 41 because it helps us. It encourages immigrants to come forward while at the same time protecting police sources.”