Two of the extremists suspected of killing an Italian activist died and a third was captured on Tuesday when Hamas security troops stormed a building in central Gaza where the men were hiding, according to the Gazan Interior Ministry.

A ministry statement said that one of the hunted men, who had Jordanian citizenship, threw a grenade at the other two — both Palestinians — to prevent them from surrendering. One was fatally injured. The Jordanian then killed himself with a gunshot to the head, the statement said. The third man, who was injured, was taken into custody.

The Italian, Vittorio Arrigoni, 36, was a pro-Palestinian activist living in Gaza. He was strangled and his body was found in an empty Gaza house on Friday, a day after a fringe group called Tawhid and Jihad claimed responsibility for his abduction. The case was an embarrassment to Hamas, which controls Gaza and maintains that it has restored security here. In the past, Hamas has protected foreign journalists and activists for the Palestinian cause.

The three men were found at a two-story house to the west of the Nussirat refugee camp. In a five-hour standoff, Hamas militants joined the security forces, who exchanged fire with three men inside for less than a minute before the grenade blast and final gunshot were heard. Three police officers were wounded.