An explosion at an army bomb disposal facility near Kabul has killed two German and three Danish soldiers. The incident is being treated as a tragic accident.

The soldiers - bomb disposal officers - died Wednesday as they tried to destroy a pair of Russian made SA-3 surface-to-air missiles. Seven others were wounded, three of them seriously.

General-Inspector Harald Kujat of the German defense ministry in Berlin said the accident happened at an official bomb-disposal facility. He said the intention had been to destroy the rockets by detonation, and all the normal safety procedures had been carried out.

But he said at least one of the rockets exploded before the disposal team was able to retreat to safety.

General Kujat added that the injured men were immediately taken for treatment to the German and French field hospitals a few kilometers away, but he said they will be brought home quickly if they cannot be treated adequately on the spot.

German defense minister Rudolf Scharping, who was on his way to Djibouti when the news broke, is returning to Berlin.

An army investigation into the incident is underway. So far nothing is known of what caused the rocket to explode, and the army is not commenting on speculation.

But General Kujat said the men were all professionals doing a very dangerous job. In the bomb disposal business, he said, nothing is routine. Everything is done carefully.