BANGKOK (Reuters) - Last month's bombings in Thai tourist towns were not linked to Muslim separatists, Thailand's defense minister said on Thursday, contradicting the police.

There has been a series of bomb attacks in the central and far south, including coordinated bombings in tourist towns in August that killed four Thai people and wounded dozens, including foreigners.

Analysts say separatist insurgents in the country's three southern Muslim-majority provinces of Yala, Narathiwat and Pattani bordering Malaysia were behind the attacks.

Tourist towns in the central south have for years been spared any spill-over of violence from the deep south and analysts say the government is loath to blame the coordinated bombings on southern Muslim insurgents because of fear of damaging tourism in the predominantly Buddhist country.

So far, two suspects have been arrested in connection with the tourist-town attacks.

"Even though the arrested suspects were from the southern provinces this is not an expansion of the insurgency and not related to southern violence," Deputy Prime Minister and Defence Minister Prawit Wongsuwan said at an event outlining the military government's achievements since a May 2014 coup.

His comments contradicted a police statement last month linking the tourist town attacks to separatists in the far south.

Thailand and Malaysia on Friday agreed to consider building a border wall to combat transnational crime and smuggling.

More than 6,500 people have died - the majority of them civilians - since 2004 in fighting between Malay Muslim rebels and Thai security forces stationed in the area.

Violence in the three southern provinces had decreased by 60 percent since the junta took power, Prawit said.

(Reporting by Cod Satrusayang; Writing by Amy Sawitta Lefevre; Editing by Nick Macfie)