Ireland ? The Ulster Volunteer Force, an underground Protestant army that terrorized Roman Catholics for decades and committed the bloodiest attack of the Northern Ireland conflict, renounced violence Thursday and promised to evolve into a force for good.

Leaders of the British territory’s Catholic minority welcomed the surprise announcement. But they also expressed skepticism, given the UVF’s hate-fueled past and criminal present as well as its breaches of its own 1994 cease-fire declaration.

The British, Irish and U.S. governments all called on UVF commanders to demonstrate their sincerity by surrendering weapons stockpiles, an act completed two years ago by the rival Irish Republican Army.

UVF members killed more than 400 Catholic civilians from 1966 to 1994, the year the group called an open-ended truce. It exploded four car bombs in the neighboring Republic of Ireland that killed 33 people on May 17, 1974 – the deadliest terror strike in four decades of sectarian bloodshed over Northern Ireland.

The UVF statement came just five days before a new Catholic-Protestant administration for Northern Ireland is scheduled to take office in Belfast, fulfilling the central dream of power-sharing contained in the Good Friday peace accord of 1998.