 -- Retail clothing store Urban Outfitters is apologizing today after selling a sweatshirt on its web site that some see as trivializing a campus shooting from the Vietnam War era.

The red faded Kent State University sweatshirt, billed by the company as a vintage find, retailed for $129 and is now listed on the site as sold out after someone purchased the company’s single available sweatshirt.

“Get it or regret it!” the company urged in its description for the article of clothing.

People on social media immediately identified the offensive connotations of the sweatshirt, pointing out that it looked blood-stained and seemed to refer to the 1970 Kent State deaths when the Ohio National Guard killed four unarmed students and wounded nine others during a protest against President Richard Nixon’s campaign to expand the Vietnam war into Cambodia.

Urban Outfitters prompted some Twitter outrage. "Just bought a bunch of stuff from Urban Outfitters yesterday. Contemplating returning it all after this disgusting sweatshirt situation," tweeted Jenna Wright. Rob Peterson added, "Hey @UrbanOutfitters, thanks for proving that History classes are actually important. Ignorance is not bliss."

Kent State University has responded to the situation through a statement that reads in part, “We take great offense to a company using our pain for their publicity and profit. This item is beyond poor taste and trivializes a loss of life that still hurts the Kent State community today.”

The company responded through Twitter, writing this morning, “Urban Outfitters sincerely apologizes for any offense our Vintage Kent State Sweatshirt may have caused. It was never our intention to allude to the tragic events that took place at Kent State in 1970 and we are extremely saddened that this item was perceived as such. The one-of-a-kind item was purchased as part of our sun-faded vintage collection. There is no blood on this shirt nor has this item been altered in any way. The red stains are discoloration from the original shade of the shirt and the holes are from natural wear and fray. Again, we deeply regret that this item was perceived negatively and we have removed it immediately from our website to avoid further upset.”

The sweatshirt is now being resold on ebay for $550 by user kentstatesweater who claims to have ordered the piece of clothing and is waiting on its arrival. The description says the owner plans to donate 50 percent of the profit to The Southern Poverty Law Center.

KSU spokesperson Emily Vincent told ABC News in an email that Urban Outfitters reached out to the university with the same statement they released on Twitter.

Urban Outfitters and ebay user kentstatesweater did not immediately return ABC News’ request for comment.