HADDON HEIGHTS, N.J. (AP) — The four-bedroom house on Sylvan Drive emerges beyond a sprawling sycamore, with steps leading to the front door past children's toys on the lawn.

It is a house like any other on the quiet block in Haddon Heights, yet on Halloween some trick-or-treaters seem to avoid the residence where Estyr Bomgardner lives with her husband, two sons, and their black Lab, Miroku.

The family bought the house in 2012, overcoming qualms they had when they learned what had happened there. The sellers turned down a higher bid because the Bomgardners could move in sooner.

Ivan Bliznetsov, ThinkStock

Twenty years ago, on April 20, the place was the scene of a horrific siege that left two officers dead, a third with years of surgeries, and neighbors traumatized. The carnage impelled police to change how they do their work.

Camden County Prosecutor's investigator John McLaughlin was shot as he served a warrant on Leslie Nelson, who lived with her parents. McLaughlin's body lay near the inside stairwell until Nelson dumped him outside.

Richard Norcross, a Haddon Heights police detective who had accompanied McLaughlin, hobbled out a side door, two fingers of his right hand blown off.

His brother, borough police officer John Norcross, was fatally shot in the head as he peered around a home across the street.

The hail of bullets came from an AK-47 assault rifle fired from the upstairs floor where now Bomgardner's sons, 4 and 6, sleep.

"We don't want to tell our kids yet," Bomgardner, 34, a special-education teacher, told The Philadelphia Inquirer. When she does, she plans to describe "someone in the house who was sick who made really bad choices."

Nelson, who was Glenn Nelson until a sex-change operation in 1992, was suspected of child molestation, which is why officers initially visited the house.

The gunfire and howls of sirens that erupted when they returned that day ended only when she surrendered 14 hours later amid a cloud of tear gas.

"I can still close my eyes on each anniversary and hear the sounds, smell the smells, see the sights," said Ronald Shute, 62, a Haddon Heights police sergeant at the time.

Most officers that day had not encountered the powerful weapon Nelson fired. Their vests were "like paper" to the bullets, an investigator said.

Afterward, the Prosecutor's Office upgraded its vests to fend off an AK-47 round. Haddon Heights and six other communities also created a tactical team - something only the larger towns had - to serve high-risk warrants.

"A lot has changed," Haddon Heights Detective Sgt. Bruce Koch said. "And it's definitely for the better."

Nelson, now 57, is serving a life sentence in the maximum-security unit of the Edna Mahan Correctional Facility in Clinton, where she does paralegal work for inmates. She declined to be interviewed.

McLaughlin's widow, Kim, lives in Haddon Heights. She has three grandchildren.

Richard Norcross is executive vice president of a computer company. His answer to what he would say to Nelson today is blunt.

"You can't print what I have to say."

Sitting in a Glassboro diner, Norcross, 49, holds out his right hand.

"The bullet went right in there, blew out both of these fingers," he says of his pinkie and ring finger. He then shows a scar next to his new fingers, which were reconstructed with bone from his hip. "They cut all this open to put new fingers in here."

The bullet also disabled Norcross' Ruger 9mm, making his vest the only protection. Nelson shot him in the chest, followed by the arm and leg.

Norcross is sure he would have been killed had Nelson's mother, Jean, not jumped into the fray and pleaded with Leslie: "You have to stop this!"

Leslie Nelson struck her mother with the rifle butt, knocking her down the steps. Nelson then walked down and shot through a wall into the kitchen, where Norcross had taken cover behind the refrigerator.

When Nelson walked back upstairs to reload, Norcross fled through a side door, his right leg bleeding profusely. An officer pulled him into a cruiser as Nelson, now reloaded, began shooting out a window.

Norcross and McLaughlin had visited the home with a child services worker earlier that day. Norcross helped Nelson's parents carry in groceries. McLaughlin, talking to Nelson, learned she had firearms locked upstairs. She refused to show them.

Nelson's attorney later said she loved her guns and lost control when police tried to take them.

McLaughlin and Norcross returned about 2 p.m., approaching the front door with three other officers. Another stood behind a tree behind the house. As McLaughlin and Norcross approached the stairs, they saw Nelson at the top, holding a gun.

She opened fire.

McLaughlin, a 37-year-old father of two girls, fell. His body was later found to have more than 20 bullet wounds.

At least 25 law enforcement agencies - and then-Gov. Christine Todd Whitman - descended on Sylvan Drive. The street was overwhelmed by gunshots, tear gas, and bullhorns. Nelson wore a gas mask and bulletproof vest.

At one point, using McLaughlin's body as a shield, Nelson dumped him near the front door.

"That was horrible," said Mike Mangold, then a prosecutor's investigator.

Norcross, who had hoped to be police chief, was in the hospital when Nelson surrendered at 4:34 a.m. Norcross' injuries left him unable to return to duty. He retired, age 29. Now with three grown children, he has had more than 20 surgeries.

The biggest pain comes from losing his brother.

"John was my younger brother, and he followed me into this job," he said.

Two tiny American flags stand next to the home where John Norcross, 24, collapsed. The woman who lives there, still too upset to talk about it, puts them up each year.

James Lynch, who prosecuted the case, prefers not to focus on Nelson but on the fallen officers' actions.

"It shouldn't be forgotten," Lynch said. "The heroism of these officers is something that should be talked about generations from now."

The house, then white, now has beige siding, added by Jean Nelson to cover bullet holes. She lived there until about 2012.

There are other subtle reminders, like some of the children who Bomgardner feels may be skipping her house on Halloween because of its history.

On the second floor, next to 6-year-old Ian Bomgardner's bedroom, they found a wall blocking off a closetlike space. Bomgardner, whose husband pulled off a panel to look inside, wonders if Nelson kept her guns there.

"It's just something that's always in the back of your mind," Estyr Bomgardner said.

There's one thing to make every authority figure from that day smile: Ian wants to be a police officer.

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