The funeral of two of the Kingsmills victims in 1976

Weapons used in the majority of IRA murders of members of the Orange Order came from American sympathisers of the terror group.

The Order yesterday demanded an explanation from the US authorities after information was passed to the institution by the PSNI's Historical Enquiries Team.

Obtained by the Order's Grand Secretary Drew Nelson, files showed the majority of weapons used to murder its members originated in the United States.

During the Troubles, 332 members of the Orange Order were killed – the vast majority at the hands of the IRA.

The information released by the HET points to the supply of American-sourced weapons in one of the highest-profile attacks on the Order, the massacre of members at Tullyvallen Orange Hall in Co Armagh in 1975.

Gunmen sprayed the meeting with automatic fire, killing four men immediately. A fifth man died later from his injuries.

Guns from America may also have been used in the Kingsmills Massacre of 10 Protestant workmen the following year.

The statistics show that a total of 266 weapons have been identified as having originated in a variety of countries, including the Eastern Bloc, Germany and England. The bulk, however, were of American origin.

The figures show that 149 (56%) of the weapons can be identified as coming from the USA.

In the case of a further 98 weapons, the country of origin could not be identified.

The first American weapon believed to have been used in the murder of a member of the loyal orders relates to the death of Francis William Veitch in September 1971.

The HET was replying to requests from the Order about the murder of their members during the Troubles.

Mr Nelson is seeking a meeting with the American Consul in Northern Ireland to discuss the "alarming revelations".

It is believed at least some of the weapons may have come from thefts at military installations.

An Orange spokesman said: "This is a very serious matter and the United States owes it to the families of those murdered to investigate how a majority of the weapons used in the commission of murder of our members appear to have been from the USA.

"The United States has set itself in the forefront of the war against terrorism worldwide, but this analysis shows an embarrassing situation which must be addressed if the US is to have any credibility in expressing opposition to terrorism."

TULLYVALLEN ORANGE HALL KILLINGS, SEPT 1975

On September 1, 1975, an IRA gang sprayed automatic gunfire inside the isolated Tullyvallen Orange hall in south Armagh, killing five men, one of whom was an 80-year-old retired farmer.

Twelve Orangemen inside the hall miraculously survived the shooting carnage. One survivor — an off-duty member of the security forces — returned fire, injuring one of the terrorists.

KINGSMILL MASSACRE, JANUARY 1976

Up to a dozen gunmen ambushed a workmen's minibus near Bessbrook as they made their way home from their shift at a textile factory.

One man, a Catholic, was told to leave by the gang before they gunned down his colleagues. Another man survived the attack, but was shot 18 times.

In 2011 an investigation by the Historical Enquiries Team concluded that the IRA was responsible for the atrocity and that victims were targeted because of their religion.

FACTFILE

Of the 332 members of the Orange Order who were killed, 78 per cent were carried out by the IRA.

Those murdered during the Troubles included 229 who were shot dead, while another 73 died in bombings.

The murders resulted in at least 550 children being left without a parent.

Belfast Telegraph