WASHINGTON, D.C. – Nearly two dozen legal, civil rights, and education advocacy organizations recently sent a letter to the U.S. departments of Defense, Justice and Education to plead with federal officials to stop sending military equipment, weapons and armored vehicles to public schools.

The move comes as an increasing number of school districts across the country take part in the Department of Defense’s Excess Property Program, commonly known as the 1033 program. The Huffington Post reports that at least 20 schools have taken in military-grade equipment, from grenade launchers to laptops, since the program started in 1997.

The equipment is given to schools, public university police forces and local police agencies free of charge, but is considered to be on indefinite loan from the government.

MORE NEWS: Know These Before Moving From Cyprus To The UK

“The recent events in Ferguson, Missouri, demonstrate the tensions that invariably develop between local law enforcement and the community when military equipment is unnecessarily deployed against citizens,” according to the letter submitted to Mark Harnitchek, director of the Defense Logistics Agency that oversees the program.

RELATED: Panic over student’s ‘military-type jacket’ sends school into lockdown

“These events also underscore the negative impact of militarization on the already tenuous relationship between communities of color and law enforcement.”

The education and civil rights advocates contend that “adding the presence of military-grade weapons to school climates that have become increasingly hostile due to their overreliance on police to handle routine student discipline can only exacerbate existing tensions, intensifying overly punitive atmospheres that criminalize and stigmatize students of color,” the letter reads.

Florida’s Pinellas County School District, for example, received almost two dozen M16 rifles, while San Diego and Los Angeles schools took in armored vehicles capable of withstanding mine explosions, according to the news site.

“Our hope is that our officers never have a need to use this equipment,” Pinellas schools public information officer Melanie Marquez Parra told the news site. “These are items we acquired so they could have equipment for worst-case scenario situations.”

San Diego Unified School District Police Chief Ruben Littlejohn told NPR the district’s mine-resistant vehicle will be used exclusively as a rescue vehicle, and that officials planned to fill it with teddy bears and trauma kits.

MORE NEWS: How to prepare for face-to-face classes

It’s not a militarization of public schools, he said.

“There will be medical supplies in the vehicle. There will be teddy bears in the vehicle,” he said. “There will be trauma kits in the vehicle in the event any student is injured, and our officers are trained to give first aid and CPR.”

Littlejohn told KPBS the vehicle, which arrived in April, was stocked with donated medical supplies and students in the district’s auto collision refinishing program repainted it, but some readers clearly disapproved of the idea regardless.

“They can call it a ‘love buggy,’ a ‘student patrol limo,’ or a ‘campus police fun bus’ and then paint it pretty colors, but that doesn’t change the fact it’s a piece of military equipment that is unnecessary and sends the message that local officials are at war with students,” according to one commenter on the KPBS site.

Other school districts in California, Texas, California, Utah, Kansas, Missouri, and Georgia have also received military-grade weapons or supplies, according to a Freedom of Information Act request filed with every state by MuckRock.com, a government transparency website. Only about half of the states have so far replied to the public information requests, the Huffington Post reports.

And at some school districts, like suburban Topeka’s Auburn Washburn Schools, local officials won’t discuss with the public what kind of equipment they’ve received.

Auburn Washburn superintendent Brenda Dietrich refused to divulge the details of that district’s 1033 acquisition yesterday, but the Topeka Capital Journal reports paperwork from the state Department of Administrations shows it was an M16 assault rifle, according to the Associated Press.

Public pressure, however, has apparently convinced officials in at least one school district to end its affiliation with the 1033 program. The Aledo School District in Texas is working to return military rifles it acquired through the program, despite assertions from police officials that the guns are a necessity.

“Police need to have the same or better equipment than the person who wants to do harm,” Jimmy Womack, chief of the Mansfield school district police, told the Star-Telegram.

A total of nine Texas school district participate in the 1033 program.

According to the Star-Telegram:

Various Texas police agencies borrowed six military helicopters, more than 40 armored vehicles and a Boeing 737, but more than 180 agencies nationwide and seven in Texas have been investigated and suspended over lost or stolen weapons, particularly assault rifles.

But the more than 200 Texas school districts operating their own campus police need the same gear as other agencies in case of an “active shooter” situation, Womack said.