Little sneaked a metal plaque to commemorate two young boys killed in a bomb attack by the Irish Republican Army in Warrington, Cheshire.
Tim Parry, 12, and Jonathan Bauer, 3, detonated two bombs in the city center on 1993, injuring 54 people and killing them.
The A3-sized plaque is considered to have scrap metal value of no more than £ 30.
Colin, the father of Tim Parry, said the theft was "not soulless, not ruthless, just very offensive ".
He said: "My reaction is not to believe that someone will be so ruthless, without any conscience, just to go down in peace and take some [least]cash]
Great emotional value.
"I find it difficult to get into the minds of people who will perform this kind of behavior.
"I appreciate many people's desire for money, times are tough, but it's hard to imagine bending over to do it without knowing what they 've got.
For this reason, their behavior is even more disgusting.
"This plaque is part of the River of Life Memorial at Warrington Bridge Street, and the Duchess of Kent opened on 1996.
Mr Parry said: "It copies a passage from the Bible with a large rock so that the water flows out of it and then flows into a dome along a passage, the whole passage was words and all sorts of things to commemorate the bombings and the boys.
He urged the people who stole it to return it, and he said: "You want them to have some thoughts in their hearts, except for the most basic thoughts, they have them now, with it, if you don't bring it back, put it where we can find it.
Police said the plaque was stolen at some point on April 20-5-5.
A committee noted its disappearance.
Employed by the warden of the town center.
Graham Davis of Cheshire Police said the plaque and monument "are very important to the town ".
He said: "We will call on anyone who has information about the theft to come forward.
He said it was "disturbing" that people in the town found the plaque stolen ".
"We will urge anyone who knows the identity of a thief --
Or the whereabouts of the plaque.
Contact us immediately.
"We will also call on anyone who may be sold a plaque to contact," he said . ".
Pastor Richard Blackburn, Bishop of Warrington, said his prayers were with two families.
He said: "It is pointless acts of vandalism that not only grieve the family, but also the whole community.
I call on all people with any information to assist the police and to help advance this investigation.
"I pray for them when they deal with this terrible news.
"Two bombs exploded within a minute of March 20, 1993.
The first was outside a boot shop and the second was outside a place packed with shoppers, outside McDonald's.
The bombing caused widespread public resentment and led Mr. Parry to establish the Tim Parry Jonathan Bauer Trust to promote greater understanding between Britain and Ireland.
Mr. Parry has also set up a peace center in Warrington, who was nominated for a peace campaign to work for the FARC.
The metal recycling industry is worth about 5.
And employs nearly 8,000 people in the UK.
It is estimated that metal theft will cost the British economy 700 pounds a year, and criminals are targeting more and more items.
From residential areas to memorial plaques for war and cemetery, slides for children's playground and fire escape stairs, there are cables, drainage covers and elevator panels.
Theft from churches is also increasing, and according to insurance company Ecclesiastical, more than 2,500 cases of theft were reported in 2011, a record high, and the company provided insurance for 97% of Anglican churches.
To reduce theft, the company is now installing alarms on the roof of some churches.