DENVER -- Nearly 30 Air Force Academy cadets required medical care, with six of them hospitalized, after an annual tradition to mark the first snowfall of the season turned into an out-of-control melee, officials said Wednesday. 
 
 An unauthorized ritual last week called "First Shirt/First Snow," in which freshman cadets try to throw their cadet sergeant into a snowbank, grew violent and resulted in injuries, the academy said in a statement. 
 
 "A relatively small number of cadets chose to take part in this unsafe activity," Brig. Gen. Gregory Lengyel said in the statement. "This incident was unacceptable." 
 
 The six cadets who required hospitalization after last Thursday's incident have all been released, and the 21 others were treated for "bruises and/or lacerations" at the academy's cadet clinic, the school said. 
 
 Lengyel, who serves as the commandant of cadets, said school officials are investigating the incident. "Our Air Force expects better. I expect better, and I'm confident the cadets will learn and grow from this." 
 
 An internal email about the incident obtained by the Air Force Times newspaper, reportedly written by Brig. Gen. Dana Born to school administrators, said the annual ritual "has turned into a brawl" between freshmen and upperclassmen. 
 
 "This ritual has devolved to become increasingly violent, with significant numbers of cadets requiring medical care over the past two years," The Times cited the email as saying, adding that the latest injuries included concussions, an arm bite and cuts that required stitches. 
 
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 “Obviously, this has gotten out of hand and cannot be repeated,” Born wrote. “There is no way we can condone or defend this.” 
 
 The Times said the internal memo indicated Lengyel might allow the tradition to continue if cadets can show it can be conducted with "good order and discipline and proper risk management." 
 
 Located in Colorado Springs, 60 miles south of Denver, the academy has an enrollment of about 4,100 cadets, and graduates are commissioned second lieutenants in the U.S. Air Force. 
 
 The reported incident is a fresh blow to the reputation of the Air Force, which has dealt with a number of scandals in recent years. 
 
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 In 2003, the academy was accused of failing to investigate numerous incidents of sexual assaults on the campus. 
 
 In 2005, an Air Force panel concluded that officers and faculty members periodically used their positions to promote their Christian faith and failed to accommodate the religious needs of non-Christian cadets. 
 
 The academy has also been hit with several cheating and drug-use incidents in recent years, according to the Colorado Springs Independent. 
 
 Reuters contributed to this report. 
 
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 Follow US news from NBCNews.com on Twitter and Facebook ||||| CHARLESTON, S.C. (AP) — South Carolina's military college The Citadel announced Thursday it is investigating after photos surfaced on social media of cadets dressed all in white with pillowcases over their heads, images that invoke the Ku Klux Klan. 
 
 "A social media posting, which I find offensive and disturbing, was brought to my attention this morning," retired Air Force Lt. Gen. John Rosa, the president of the college, said in a statement. 
 
 The statement said the school has started proceedings to suspend the eight students involved. 
 
 The college said the seven students wearing the pillowcases were knobs — freshmen who get that name from the close-cropped haircuts they receive when they report to school. The eighth student in the photos is an upperclassman. 
 
 The photos show the knobs wearing both white T-shirts and white pants with the pillowcases on their heads. 
 
 "Preliminary reports are cadets were singing Christmas carols as part of a 'Ghosts of Christmas Past' skit," Rosa's statement said. 
 
 University spokesman Brett Ashworth said "at this point, there is no evidence that this was hazing." He said the college is looking into both who took the photograph and how it came to be posted on social media sites. 
 
 He added cadets are now taking final exams and the investigation will likely not be completed until after the first of the year. The college's military Corps of Cadets has 2,300 students. 
 
 Under the school's system, freshmen receive rigorous military training administered by upper-class cadets. 
 
 Hazing has from time to time put the college in the limelight and novelist Pat Conroy wrote about it in his book "The Lords of Discipline" — a fictional account based on his Citadel experiences in the 1960s. 
 
 In 1986, five white cadets entered the room of a black cadet dressed in sheets and towels and left a charred paper cross. The black cadet left the college and later about 200 people, many of them black, marched in protest.
– An Air Force ritual devolved into an all-out melee last week that left 30 cadets injured and six hospitalized—with concussions, cuts, and an arm bite, NBC News reports. It was all part of the unauthorized "First Shirt/First Snow" ritual, in which cadets toss a sergeant into a snow bank at the Air Force Academy in Colorado Springs, Colo. Not too surprisingly, the rite has led to melees and injuries the past couple of years. "Obviously, this has gotten out of hand and cannot be repeated," wrote Brig. Gen. Dana Born to school administrators. Just how does the ritual turn into a massive melee? When "upperclassmen defending the first sergeant" begin brawling with "the four degrees trying to capture the first sergeant," wrote Born, according to the Air Force Times. But a new commander at the school says he may allow the sergeant-tossing to continue if cadets can do it nicely. "Our Air Force expects better," says Brig. Gen. Greg Lengyel. "I expect better, and I’m confident the cadets will learn and grow from this."