MONTREAL (Reuters) - A young Montreal couple tried to use Christmas lights and sandpaper to make a homemade bomb, a prosecutor told a Canadian court on Wednesday in opening statements in the terrorism trial of the former college students.

The items and a handwritten bomb-making recipe copied from a propaganda magazine published by al Qaeda militants were found after the Royal Canadian Mounted Police searched a condo rented by El Mahdi Jamali and Sabrine Djermane in 2015, prosecutor Lyne Decarie said in Quebec Superior Court in Montreal.

It is not clear how the lights would have been used to make a bomb.

Jamali, 20, and Djermane, 21, have pleaded not guilty to charges of trying to leave Canada to join a terrorist group, possessing an explosive substance, facilitating a terrorist activity, and committing an offense for a terrorist group.

The 2015 arrest of the couple, teenagers at the time, came at a time when international security forces reported that waves of young people, including college students from Montreal, were heading to Syria to join Islamic State militants.

Decarie said investigators found other materials, jihadist propaganda and evidence that the couple had watched a video by a Canadian fighter for the Islamic State. New luggage and clothes, along with passport applications were discovered during the search.

The pair reiterated their not-guilty pleas before Decarie began her remarks and then listened from a high-security prisoners’ box that was enclosed in thick glass.

RCMP began investigating the couple after receiving a tip, Decarie said, and arrested them days later.

The prosecutor said she would call family and friends of the accused as well as police experts in terrorism and explosives as witnesses in the trial, which is expected to last 10 weeks.