A French art college has apologised after a photograph of white students was digitally manipulated to make some look black in an attempt to broaden the college’s appeal in the US.

Former students of the private Émile Cohl art school in Lyon flagged up on social media that a picture taken of a group visit to a gallery had been doctored on a promotional website for the college in the US.

In the original picture, none of the students were black.

The original photo. Photograph: Twitter

In the promotional material, among other manipulation, three students’ faces had been darkened and two people of colour were added to the picture.

The manipulated photo. Photograph: Twitter

After people on social media criticised the use of photo manipulation instead of giving college places to black students, the school apologised and said it had been unaware of the manipulation, which it said was carried out by a communications agency in the US.

La photo de base est trouvable sur leur twitter en plus, mon dieu pic.twitter.com/HzF9PVUghe — Ameliabrador (@ameliabrador) September 9, 2018

Antoine Rivière, the college director, told L’Express he was only made aware of the altered photo when he was contacted by some fifth-year students who appeared in it.

“We had sent a certain number of documents to an American communications agency in order to highlight our college,” he said. One of the photographs had been doctored without the school’s knowledge.

The school had immediately ordered the page to be taken down and apology letters were sent out to students and parents.

“This is the opposite of what Émile Cohl represents,” Rivière added.

The school is planning to open a branch in the US in the near future.