Surveillance photos released yesterday show the suspect enter the store, and leave a mass murderer.
Pharmacy video captures every step of psycho's execution spree

They didn't put up fight -- and he still slaughtered them.

Chilling surveillance video at the tiny Haven Pharmacy in Medford, LI, captured the horrific Father's Day bloodbath that left four dead -- and law-enforcement sources yesterday described how the killer "executed" his innocent victims without making any demands.

"This is one of the most heinous, brutal crimes we have ever encountered," said stunned Suffolk County Police Commissioner Richard Dormer yesterday.

All four victims "offered no resistance -- and did not appear to provoke the shooter in any way," Dormer said.

"They were all shot at close range. They were shot very suddenly and very quickly."

The stunning footage shows the baseball-capped fiend first strolling into the tiny mom-and-pop shop at about 10:20 a.m. Sunday, only minutes after druggist Raymond Ferguson, 45, had opened up the Southaven Avenue store along with a cashier, 17-year-old Bellport HS senior Jennifer Mejia.

Mejia wasn't supposed to be working that day -- her sister, also an employee, had already taken the day off. But Mejia volunteered to cover Father's Day for an older male co-worker who has kids.

She and Ferguson were standing behind the drug counter when the nervous, scrawny robber -- an addict hunting his drug of choice, oxycodone -- opened a door to the enclosed area where they were and entered.

Without hesitation, the deranged druggie then "executed the workers" in cold blood, a law-enforcement source said.

Then, within minutes, two unsuspecting store patrons entered the shop.

Byron Sheffield, a 71-year-old grandpa, had come in to get his usual prescription. Jamie Taccetta, a 33-year-old physical therapist and mother of two, was making a quick pit stop at the shop to pick up thyroid medication.

Taccetta's fiancé -- whom she was set to marry Oct. 15 -- was waiting for her in their car outside in the parking lot.

"Two customers walk into the store -- they're not thinking that it's their last day on Earth," Dormer said.

The gunman -- a weasly figure sporting a backpack, beard and sunglasses -- calmly walked to the front of the shop, where Taccetta was standing at a counter and Sheffield was in a nearby aisle.

The killer then pumped a single bullet into the back of the head of Taccetta without saying anything, her family said.

And still without uttering a word, he shot Sheffield, too.

Taccetta's corpse landed over the drug counter, while Sheffield collapsed near some shelves, a source said.

The gaunt gunman then began stuffing oxycodone pills into his black backpack and fled back out the front door -- making sure he shoved his white baseball cap down over his face as he left, sources said.

One shaken law-enforcement source called the video footage "disturbing."

Taccetta's fiancé, James Manzella, who was the first to come upon the carnage, described in heartbreaking detail what he saw after entering the shop looking for her.

Concerned that Taccetta was taking so long in the shop -- and seeing a shifty-looking man leave in the meantime -- Manzella went inside and spotted her body slumped over the counter, as well as Sheffield's in the aisle, he told The Post.

Manzella became hysterical, sobbing, and bent down to help her, the video shows. But seeing that she was lifeless, he pulled out his phone and frantically called 911.

Police yesterday continued their massive manhunt for the killer.

"We have not identified [a suspect] at this point," Dormer said

Employees of a 7-Eleven in Patchogue -- just over a mile from the pharmacy -- called cops yesterday morning to report that a bearded man who looked strikingly like the killer seen on the pharmacy surveillance images had been in that convenience store several times in the past month, as recently as five days ago.

"He looked liked that," said a source about the man. "Right down to the baseball cap.

"He looked strung out. You could tell he was a drug addict," the source added. "He was quiet. He came in and bought some Vitamin Water."

At one point, the cops visited a nearby motel to look for the man but didn't find him.

Police also detained several people on suspicion they might be the killer -- but none of them were him.

Dormer said cops were canvassing area drugstores and doctors to see if any of them had recently dealt with a person urgently seeking of oxycodone.

"We have evidence that is assisting with the investigation," he said, refusing to elaborate.

Mejia's family priest, the Rev. Freddy Lozan, said: "The man who did this was crazy. He killed four innocent people."

Lozan said the girl had helped him distribute Communion at Mass the night before she was killed.

"Saturday night, she offered the bread and wine, and the next day she gave her life," the priest said. "No one expected this. No one understands this.

"I told her family she's with God," he added. "They're completely devastated . . . the mother's going crazy right now."

Mejia's dad, Rene, said about his daughter's killer: "I don't hold any anger. God will take care of it . . . We have to go on.

"We're doing badly. Leslie's doing badly. All we can do is pray," the dad said. "We are no one to ask for revenge. We want people to remember her as a great person, well-educated . . . She was well-loved."

Haven Pharmacy worker Edmund Tam, whose regular Sunday shift was filled by Mejia, told The Post, "Of course, I feel very lucky. But at the same time, that girl didn't deserve this.

"She was a sweet, beautiful girl, and this is just a tragedy," said the 37-year-old Tam. "That's more important to me than feeling luck. I feel terrible for her family."