Cambodia fired mortar shells into the border province of Ubon Ratchathani early Tuesday, Thailand said, injuring a Thai soldier.
Later in the day, however, the Thai military said it had received information that the attack was due to an operational error.
According to Cambodia's Ministry of Defense, two Cambodian soldiers were injured when an explosion occurred in a pile of garbage.
The years-long conflict between the countries was revived last year, with recurring periods of fighting - and ceasefires - and on December 27, the parties signed a new ceasefire agreement.
The fighting in December killed several people and forced about a million people to flee.
