The Tories have admitted that a member of staff raced to edit a Wikipedia entry after David Cameron made a dubious assertion in the House of Commons.
The Wikipedia entry change was traced to the Conservative Party HQ
Renaissance painter Titian had his biography altered on the online encyclopedia following a disagreement between Gordon Brown and the opposition leader over his age when he died.
Titian came up in Wednesday's Prime Minister's Questions as Mr Cameron asserted that Mr Brown never got his facts right.
"You told us the other day you were like Titian aged 90. The fact is Titian died at 86," the Conservative leader said.
Within minutes, a Wikipedia user registered at Conservative party headquarters logged on and changed Titian's date of death from 1576 to 1572 to conform with Mr Cameron's declaration.
A party spokesman blamed the editing on "an overeager member of staff putting right an incorrect entry on Wikipedia."
Mr Brown had brought up Titian last month as he discussed learning to deal with the global economy.
"I'm reminded of the story of Titian, who's the great painter who reached the age of 90, finished the last of his nearly 100 brilliant paintings and he said at the end of it, 'I'm finally beginning to learn how to paint,' and that is where we are," he said.
Scholars are unsure at what age Titian died - most believe he was born between 1486 and 1490 and died in 1576.
By Wednesday evening, the date of death on Wikipedia had been changed back to 1576.