In a trend of growing concern to police, more and more real guns are being painted in fluorescent colors that make them look like toys.
At the same time, growing numbers of toy guns that fire pellets are being produced to look just like lethal weapons.
"You can't tell the real from the fake anymore," Camden County Prosecutor Joshua Ottenberg said. "It's literally a miracle that some kid here hasn't been shot dead yet."
On Thursday night, a distraught man carrying a fake gun closed down the Walt Whitman Bridge for nearly four hours.
Troopers seized the man's "very realistic" weapon after he surrendered. "It looked like a SIG Sauer, just like the ones we carry," said Sgt. Stephen Jones, a New Jersey State Police spokesman. "There's no telling what could have happened if he had pulled it out."
Last month, an FBI bulletin warned police across the country about a new process that can produce or tint weapons in garish colors. Under the headline "Not a toy gun," the bulletin featured a dozen photos of guns with candy-colored finishes.
Often, the colors are used to appeal to women and young sport shooters.
Smith & Wesson offers the LadySmith, a pink, .38-caliber revolver designed for women. Remington sells a child-size shotgun decorated with pink and black swirls. Crickett, a Pennsylvania company, sells a .22-caliber rifle for youths - the Davey Crickett - that's red, white and blue.
For $200, Jim Astle, owner of Jim's Gun Supply in Wisconsin, will color a gun to the owner's whim. Last year, he got international attention after he customized an AK-47 in Pepto-Bismol pink. Emblazoned on the gunstock was the children's cartoon character Hello Kitty.
"One of our soldiers in Iraq wanted it as a surprise present for his wife so she could shoot it at the range," Astle said.
This month, Lauer Custom Weaponry of Wisconsin introduced a line of gun-customizing kits. It's called the Bloomberg Collection, after New York Mayor Michael Bloomberg, who urged passage of a 2006 law that makes selling, possessing or using gun-paint kits a crime in the five boroughs.
The Lauer kits come in Manhattan Red, Bronx Rose, Staten Island Yellow, Queens Green and Brooklyn Blue.
Steve Lauer, who said militaries and governments around the world used his DuraCoat process to protect guns from corrosion, is miffed that Bloomberg has called his product unsafe.
To goad the mayor, he said, a caricature of Bloomberg's face comes on the barrel.
Bloomberg condemned Lauer's company last week, calling the colored guns "a slap in the face to our men and women in the Police Department."
Bloomberg said the guns would be confused with toys.
"A police officer won't be able to tell the difference," he said. "It's a tragedy in the making."
"Let us just pray that nobody gets killed over this. This is an outrage," Bloomberg said, singling out Lauer. "It defies imagination how anybody could be so venal."
Legislators in Nassau County, N.Y., introduced legislation last week to ban the colorization kits.
Law enforcement officials also are not laughing.
"Introducing weapons painted to resemble children's toys creates a hazard for everyone," said Jones, of the New Jersey State Police. "You no longer can assume that a wildly painted gun is a toy."
Philadelphia police have confiscated only one colorful gun, said Sgt. Andrew Little of the firearms identification unit.
"We got one called the Pink Lady, a pink revolver marketed to women," Little said. "It looks like a toy."
"My concern right now is the fake guns that are passing as real guns," he said. "They're being used in crimes, and they look authentic."
Last year, Philadelphia police confiscated 823 fake guns, up from 654 in 2006. In the last four years they have seized 3,091 replicas and toys, a police spokeswoman said.
Little said he had seen exact replicas of "just about every semiautomatic pistol you can imagine, every make, every model. We even get exact duplicates of police service weapons."
Called "airsoft weapons," the replicas are spring-loaded and fire plastic pellets larger than those of a BB gun. They are often used in an increasingly popular military simulation game similar to paintball.
Airsoft guns can be bought without a license at many sporting-goods stores, but not in Philadelphia. The city is among at least a dozen counties and municipalities nationwide that ban their sale.
Around the country, several people have been shot dead after waving the replicas at police.
A SWAT officer in Florida killed a 15-year-old boy in 2006 as the teen brandished a replica at his school. Federal law requires toy guns to have an orange tip on the barrel, but the one on the boy's gun had been removed.
Also that year, police in Warminster fatally shot a 21-year-old man after he threatened officers with an airsoft-type replica Walther PPK.
"The frightening fact," said David Zellis, first assistant district attorney in Bucks County, "is there is absolutely no way a police officer could tell he didn't have a gun."
Last year, a third grader was suspended after she took an airsoft Luger pistol to an Upper Darby elementary school. The 8-year-old told police that she carried it "for protection." School officials thought it was authentic.
Airsoft guns are big business on the Internet.
Jonathan Lanciano, 19, turned his passion for airsoft war games into an online business - UOarmory.com - which he runs from his home in Philadelphia's Bridesburg neighborhood.
Lanciano takes orders for the guns, which are shipped to buyers directly from the manufacturers.
"We don't stock in Philadelphia, and we can't ship from Philadelphia," he said. "But everything the military has, we basically have" copies of.
Lanciano acknowledged that the required orange tips rarely stayed on.
"It's against the law to take them off," he said, "but people do. You can pull them off with pliers or paint them with black fingernail polish. Orange isn't the best camouflage color."
Philadelphia District Attorney Lynne M. Abraham warned that a police officer would be unlikely to ask whether a gun was real or not:
"I can tell you if you pull out a real-looking weapon and point it at a cop, you're a dead person."