Qatar has convicted five people, including one of the country's diplomats, over a mall fire last year that killed 19 people, including 13 children at a daycare center caught in the blaze.

Investigators have blamed faulty wiring for the May 2012 blaze.

The International Trade Union Confederation, which has followed the case, says five of those convicted on Thursday were sentenced to six years in prison each.

They included the childcare center co-owners, Sheik Ali Bin Jasim Thani Al Thani and his wife. Al Thani serves as a Brussels-based diplomat.

An assistant mall manager and an employee of the trade ministry also got six years. A fifth suspect received a five-year sentence. All are free on appeal.

The dead children included triplets from New Zealand and three Spanish siblings.