A number of wreaths and flowers laid at the Teebane memorial between Cookstown and Omagh have been destroyed in an early moring attack.
Police say wreaths and flowers laid at the memorial were scattered on the road and destroyed by passing vehicles in the early hours of this morning.
Eight Protestant workmen were killed in the IRA massacre in January 1992.
The memorial has been attacked a number of times in the past.
Ulster Unionist Councllor Trevor Wilson said it was clearly an act of wanton vandalism and should be condemned by any right thinking person.
“This is not the first time this memorial has been attacked and I appeal to anyone who has any information to inform the police immediately,” he said.
Police investigating the incident are appealing for information.
They believe the wreaths were thrown across the road between 1.30am and 7.30am.
Anyone with information is asked to contact police in Magherafelt on 101 or Crimestoppers anonymously on 0800 555 111.