Red shirt leader Jatuporn Prompan has threatened lawsuits against anyone who tries to link his movement to the bomb blasts and arson attacks in the southern provinces last week.
Mr Jatuporn said the UDD condemned the people behind the attacks but denied his group or its supporters had any link to the incidents.
He said government officials and some media were seeking scapegoats because the attacks occurred in provinces known to support the People's Democratic Reform Committee and the Democrat Party.
He was speaking at a news conference after a group of 20 armed soldiers reportedly arrested Wichai Padungsaksri, 60, a UDD leader in Ang Thong province, at his shop which sells loud speakers in Pho Thong district early on Saturday morning. Earlier on Friday night, an unidentified man had called a local hospital to make a bomb threat.
An officer claimed the group was part of the NCPO’s peacebuilding force and had been ordered to search four undisclosed locations in the province, but did not mention if Mr Wichai's arrest was connected to the bomb threat at Pho Thong hospital or the attacks in the southern provinces. The soldiers seized Mr Wichai’s mobile phone and the phones of all his family members, Ban Muang newspaper reported.
Mr Wichai’s family on Sunday said they could not reach him and were concerned. They said they had asked local police to put the incident in their local report log.
Mr Jatuporn said the arrest of Mr Wichai was one example of an attempt to connect the red shirts to the attacks.