Democratic presidential candidate John Kerry has lashed out at a veterans group that accused him of lying about his combat record during the Vietnam War.

Speaking to a group of firefighters in Boston, Senator Kerry said he has had enough with attacks from a group known as "Swift Boat Veterans for Truth," which has accused him of lying about his war record.

"Thirty years ago, official Navy reports and every person there documented my service in Vietnam and awarded me the Silver Star, the Bronze Star and three Purple Hearts," said John Kerry. "Thirty years ago this was the plain truth. It still is and I still carry the shrapnel in my leg from a wound in Vietnam."

Senator Kerry also made another appeal to President Bush to denounce the television ads put forward by the veterans group.

"They are a front for the Bush campaign and the fact that the president will not denounce what they are up to tells you everything that you need to know," he said. "He wants them to do his dirty work."

White House and Bush campaign officials have said in the past and repeated again on Thursday that they believe Senator Kerry served honorably in the U.S. Navy during the Vietnam War. But they also said that they have no connection to the veterans group attacking the Massachusetts Democrat.

The group's ad has been broadcast over the past several weeks.

"John Kerry has not been honest about what happened in Vietnam," it said. "He is lying about his record."

Bob Elder is one of the leaders of the Swift Boat Veterans for Truth. He says many Vietnam veterans are still angry over statements John Kerry made in the early 1970s about alleged atrocities committed by U.S. troops in Vietnam.

"He betrayed all of us when he came home and went in front of the Congress of the United States and accused all of us of war crimes," Mr. Elder said. "That is not what a war hero is made of."

Earlier this week, several Vietnam veterans who served with Senator Kerry rallied to his defense in light of the recent attacks on his record.

Fred Short served with John Kerry on the Swift Boat he commanded in 1969.

"I am here in front of you today because of what Senator John Kerry did that day in leading a landing party ashore and taking out the combatant with an RPG [rocket propelled grenade] who was going to take me out," he said. "If it was not for John Kerry, my name would be on a wall [Vietnam Memorial]."

The Kerry campaign released a new ad of its own praising the senator's service in Vietnam. It comes on the heels of another pro-Kerry ad by a group not affiliated with the campaign called that contrasts John Kerry's service in Vietnam with President Bush's tenure in the Air National Guard in the early 1970s.

"This election is about character," said the ad. "It is between John Kerry, who left no man behind, and George Bush, who simply left."

With the war on terrorism a major issue in this year's election, Senator Kerry highlighted his war experience during the Democratic National convention and President Bush often emphasizes his credentials as a "war president" as he campaigns around the country.