CLEVELAND (Reuters) - Teen apparel retailer Urban Outfitters apologised on Monday after criticism for selling a vintage Kent State University sweatshirt that appeared to be splattered with blood-red dye in a look reminiscent of the infamous 1970 shooting of students during an anti-Vietnam War protest.

Images of the sweatshirt quickly circulated online and drew immediate response from Kent State University and survivors of the shooting by National Guard soldiers that killed four students. They said the retailer was exploiting a tragedy for publicity and profit.

"This item is beyond poor taste and trivialises a loss of life that still hurts the Kent State community today," the university said in a statement.

The one-of-a-kind US$129 (S$163) sweatshirt, with splotches of dark red across the chest and holes, was faded by the sun but was not blood-stained or altered to look as if it had been, Urban Outfitters said in a statement posted on Twitter.

The company said it pulled the sweatshirt image from its website.

Images of the sweatshirt widely circulated on the Internet and sparked outrage in online forums.

"Urban Outfitters sincerely apologises for any offence our Vintage Kent State Sweatshirt may have caused," the company said. "It was never our intention to allude to the tragic events that took place at Kent State."

National Guard soldiers fatally shot four students and wounded nine on May 4, 1970, in a shooting that followed several days of anti-war protests on the campus. The incident was immortalised in a Crosby, Stills, Nash and Young song called "Ohio".

Alan Canfora, one of the nine people wounded at Kent State in 1970, said on Monday that he had spoken to family members of the victims and they are very upset at Urban Outfitters and do not accept the company's apology.

"This was a crass attempt at free publicity and a very morbid offering to stir up controversy," Canfora said.

Urban Outfitters has attracted public criticism over other controversial items, including T-shirts with the words "eat less" printed across the chest. Actress Sophia Bush in 2010 said the shirts glorified eating disorders and called for a boycott. Last year, the retailer pulled a series of shot glasses and flasks that resembled prescription pill bottles after lawmakers said the items promoted drug use.