Stephen “Luke” Atkinson and his Australian colleague Trent Lee worked for Norwegian People’s Aid, which helps remove unwritten ordinances left on the Pacific front of World War II.
It was not specified whether the two men were trying to defuse an aircraft when they died Sunday night in the town of Honiara.
The NPA – which has 1,850 “deminers” working in 19 countries – has suspended operations in the region while the investigation unfolds.
Mr Atkinson and Mr Lee had worked on a project to create a database of the explosives remaining on the islands.
NPA General Secretary Henriette Westhrin said: “We are devastated by what has happened and for the loss of two good colleagues. Our thoughts and deepest condolences go out to their families, parents and staff. ”
An NPA statement added: “It is a tragic accident. So far we know there has been an explosion with deadly consequences.
“Our main priority now is to offer assistance to parents and colleagues and to clarify what has happened.
“NPA’s activities in Solomon Islands have been temporarily suspended, and NPA is working with the Royal Solomon Islands Police who are investigating the incident.
“The accident took place in the Solomon Islands, where NPA is helping the government develop a centralized database that provides insight into the large amounts of explosive remnants of war contamination dating from World War II. ”
The Foreign Office has been contacted for comment.