Students at a university in Canada have been accused of cheating - in an ethics exam.

The students are all engineers at Carleton University, Ottawa, who have to do the ethics paper as part of their fourth year - one of the few essays they have to write.

Thirty-one students are reported to be under investigation over allegations that they used essays obtained from the internet.

A university student guide warns: "Plagiarism is a serious instructional offence, and may result in failing a course, a reprimand, and mandatory withdrawal from the university."

Associate dean Donald Russell told CBC television: "Some of the offences involve the entire document submitted, so they've taken parts of different websites, assembled them into an essay and submitted it as their own work."

Check

In one case, he said, a student had changed just four words in an essay taken from a website.

A member of staff did a comparison check.

One of the students in the class, Paul Paquette, told the university's student newspaper he was shocked at the number involved.

"I was surprised that so many people could do something so obviously stupid," he said.

But the course co-ordinator, Ata Khan, was not surprised.

"This kind of thing is happening around the country. It happens all the time," he told the newspaper.