Updated

Prosecutors in Mauritania are seeking to lengthen the sentence of a Canadian man who is imprisoned for alleged links to terror groups.

Aaron Yoon, 24, was convicted last July on charges of having ties to a terrorist group and of posing a danger to national security.

He's served nearly half his two-year sentence, but now Mauritanian officials are seeking to lengthen it to 10 years.

A judicial official who insisted on anonymity because he was not authorized to speak to journalists said Tuesday that the new charges stem from Yoon's connections to two other Canadians involved in a terror attack on an Algerian gas plant.

The three were once friends and attended the same London, Ontario high school.