Families and friends have laid wreaths at the unveiling of a memorial to the seven victims of the first IRA bombing on the British mainland 50 years ago.

An emotional service was held to bless the new memorial which has been created on the site of the HQ 16th Independent Parachute Brigade Officers’ Mess in Aldershot, which was targeted on February 22 1972.

The service was held at the same hour as the explosion which could be heard across the Hampshire town.

An Army spokesman said: “At 12.15 on February 22 1972 the garrison town of Aldershot was rocked by a massive explosion as a Ford Cortina packed full of explosives detonated outside the 16th Parachute Brigade Officers’ Mess.

“It had been intended to kill and maim officers of the Parachute Regiment and Airborne Forces whilst they were at lunch, but it is thought to have gone off prematurely and in so doing, took the lives of a gardener, five civilian members of the mess staff and an Army Chaplain.

“The following day, an announcement from the Official Irish Republican Army in Dublin stated that this was in retaliation for the events that took place in Derry on January 30 that would later become known as ‘Bloody Sunday’.

“It was to be the first atrocity committed on the UK mainland as a result of the Northern Ireland troubles.”

Brian Bosley, from Featherstone, West Yorkshire, laid a wreath in memory of his mother, Thelma Bosley, 44, a cleaner who was killed in the blast.

He told the PA news agency: “It was 50 years ago but it still hurts.

“The only thing I have got is she didn’t feeling, one minute she was talking and the next minute she wasn’t talking.

“I feel sad for the people lost here, five women, a gardener and a Catholic priest. They didn’t achieve anything – what was achieved?”

Grace Donnelly, from Liverpool, lost her best friend, Margaret Grant, a mother-of-three, in the bombing.

She said: “It’s a wonderful tribute to give to them, they went there to do their job and then this awful thing happened.

“It’s very emotional, she left three little boys behind, she was only 32 and I was her best friend.

“I was down in the town having lunch and we heard this terrific explosion and first thing my friend said was: ‘That’s a bomb.’

“We ran up the hill and there were police and ambulances were here. The regimental sergeant major came up to me and said: ‘We have some terrible news’, and that’s when he told me about Margaret.

“Then we had to tell the young boys. It was a terrible time.

“I will never forget it – it was as if it was last week.”

Each side of the heptagonal memorial plinth represents one of the victims: gardener John Haslar, civilian mess staff Jill Mansfield, Thelma Bosley, Margaret Grant, Cherie Munton and Joan Lunn, and Army chaplain Father Gerard Weston MBE.

Following the service, a parade and march was held along Aldershot’s Queen’s Avenue, which was closed to traffic for the first time in more than a decade for the event.