Thailand said Tuesday that Cambodia violated their hours-old cease-fire that ended days of fighting between the neighbors over their disputed border.

The talks between commanders on both sides were seen as a crucial test of whether the cease-fire deal reached on Monday would result in a lasting peace.

The leaders of Thailand and Cambodia have agreed to an “unconditional cease-fire” set to go into effect at midnight following five days of deadly clashes over their disputed border, Malaysian Prime Minister Anwar Ibrahim said Monday.