Troops in nearby border provinces were placed on high alert as the capture of the five Thai rangers raised fears that the conflict could widen.

The five soldiers, who were based near Cambodia's Keo Sikha Kiri Savara pagoda, were detained by Cambodian troops.

The fighting included artillery exchanges and small arms fire, and partially destroyed communities on Thai soil.

The cross-border flare-up erupted about 3:15 PM, a few hours after Foreign Minister Kasit Piromya and his Cambodian counterpart Hor Namhong met in Siem Reap and pledged to avoid violence in resolving border disputes.

Cambodian Information Minister Khieu Kanharith claimed the fighting erupted when Thai troops ignored warnings to stop crossing into its territory.

But Thailand disputed that account.

Army spokesman Sansern Kaewkamnerd said the clash was triggered by artillery rounds from the Cambodian side that fell on Thai territory.

Thai army spokesman Col Sansern said the detention of the Thai soldiers might have stemmed from a misunderstanding.