Warning: This story contains offensive language

Carleton University in Ottawa says an investigation is underway after photos of students wearing shirts with “inappropriate wording” surfaced online on Sunday.

Images of students wearing the shirts were making the rounds over social media after an Ottawa lawyer tweeted a photo reportedly taken near the university’s campus.

The shirts had the words “FUCK SAFE SPACE,” apparently referring to campus safe spaces where students can be free from sexual harassment and homophobia.

Leslie Robertson tweeted a photo of two men wearing the T-shirts while walking along a sidewalk. It was retweeted more than 140 times.

And to clarify there were many people, including women, wearing these shirts — Leslie Robertson (@GalldinRoberts) September 7, 2014

The Charlatan, Carleton’s independent newspaper, reported that photos of frosh leaders wearing the shirt have also been posted on Facebook, Twitter and Instagram, but the images have since been deleted.

There was speculation online that the shirts were worn in protest of a university rule prohibiting swearing during frosh week.

In a statement, Carleton University said it is investigating “an off-campus gathering Sunday involving Carleton students who wore T-shirts with inappropriate wording.”

University policy “prohibits activities” that contravene the guiding ethics of the institution, the statement said.

“Carleton University is a community of respect and all efforts are made to ensure that those within our community are respectful of their fellow students, the broader community and the university itself.”

The university-sanctioned Fall Orientation Week at Carleton wrapped up on Saturday.

The incident sparked anger over Twitter on Sunday:

Wow... Our @Carleton_U frats have some ways to go. MT @GalldinRoberts: Frat party at #Carleton "fuck safe space"?!! pic.twitter.com/ys8fciW6wd — Philippe de Montigny (@MPdeMonti) September 7, 2014

Imagine your introduction to university activism was a #FuckSafeSpace campaign. — Rosella Chibambo (@Chibambo) September 7, 2014

If this is a "wah, you're ruining the fun because I like to say fuck and shit", well, wah. I like to swear, too, but not in my classroom. — Lucia L. (@empathywarrior) September 7, 2014

Yayyyy another frat chapter from Carleton making an ass out of themselves. Those 'Fuck Safe Space' shirts are disgusting. — Biancé (@thatbianca) September 7, 2014