The number of deadly weapons found in city schools has climbed for the third straight year, and the problem is worse than previously reported, The Post has learned.
Last school year, 2,120 weapons were seized from students, including 10 firearms, 1,176 knives, 607 boxcutters and razors, 53 BB guns, 34 stun guns and 240 other dangerous objects.
The total was 3.3 percent more than the 2,053 weapons seized the year before, and up from 1,673 in 2014-15, the NYPD said Friday in the wake of a fatal stabbing at a Bronx high school.
Since Mayor de Blasio took office in 2014, weapons seizures have surged by 26.7 percent.
In the three weeks since classes started Sept. 7, schools have already confiscated 196 weapons, including one firearm, 119 knives, 47 boxcutters or razors and three stun guns, the NYPD revealed.
Wednesday’s classroom slaying — the first school killing in nearly 25 years — came two months after de Blasio held a press conference to trumpet a drop in school crime, calling the 2016-17 year “the safest on record in the history of New York City.”
But the city was citing confusing, even misleading, data, The Post has learned.
The weapon-confiscation numbers given out by an NYPD official at the Aug. 1 news conference were 48 percent and 91 percent lower than actual tallies in the last two years.
In response to a reporter’s question at the press conference, NYPD Assistant Chief Brian Conroy, commander of the school safety division, said the number of weapons found in schools had risen from 1,073 in 2015-16 to 1,429 in 2016-17.
After repeated inquiries by The Post, the NYPD press office explained that Conroy was referring to “incidents” in which weapons were seized, not the total number of weapons. A spokeswoman blamed the media, including The New York Times — which again reported the faulty numbers last week — for getting it wrong.
But a video of the press conference shows Conroy never used the word “incidents” when a reporter asked about “weapon recovery.”
“This year, we had a total of 1,429 weapons recovered, weapons and dangerous instruments,” Conroy said. “The prior year in 2015-16 was 1,073.”
Wednesday’s killing occurred at the Urban Assembly School for Wildlife Conservation, which did not have metal detectors.
In a history class, Abel Cedeno, 18, whipped out a 3-inch switchblade and allegedly stabbed Matthew McCree, 15, in the chest, killing him. He also allegedly knifed Ariane LaBoy, 16, who survived.
The two wounded boys had been pelting Cedeno with pencils.
“I guess I just snapped,” Cedeno told The Post in a jailhouse interview Friday.
Cedeno said other kids had taunted and bullied him about his sexuality since the sixth grade, and called him “f—-t” and other slurs in the halls of the 585-student Tremont high school.
At the August press conference, de Blasio credited vigilance by safety officers and school staff for the rising weapon seizures. The administration has been studying the possibility of removing metal detectors from schools to avoid a jail-like atmosphere.
But Gregory Floyd, president of the school safety agents union, Teamsters Local 237, blamed a lax disciplinary system that discourages arrests and suspensions.
“They don’t arrest kids for these offenses, which means children are bringing weapons to protect themselves,” Floyd said.
He called for metal detectors in all high schools, and an evaluation of junior highs to see whether they are needed.
Scanners were installed at the Urban Assembly School on Thursday, a day after the killing.