More traces of explosives have been found on the migrant ship that brought 76 Sri Lankan Tamil men to Canada last month, a Canada Border Services Agency officer has testified.

The explosive RDX – also known as cyclonite or hexogen – is used to make plastic explosives, mainly for the military. Its residue was discovered in three separate parts of the Princess Easwary, which was intercepted off the coast of Vancouver Island on Oct. 17.

Traces of two other explosives were found on two items of clothing seized when Canadian authorities boarded the ship and took the migrants into custody.

This latest revelation – made at a detention hearing before the Immigration and Refugee Board – is potentially damaging to the migrants, all of whom claim to be Tamil refugees fleeing persecution in Sri Lanka. Border officers who scoured and swabbed the ship came up with 10 positive results for traces of explosives.

Some terrorism experts – including a scholar who is the main adviser to the Canadian government in the case – have alleged that at least two of the men are members of the LTTE. There have also been allegations that the migrants' ship was previously a Tamil Tiger gun-running vessel that transported weapons from North Korea to Sri Lanka, reported the Globe and Mail news.