QUITO, March 22 (Xinhua) -- Ecuadorian President Rafael Correa warned Saturday that diplomatic tension with Colombia could rise again if Colombia's cross-border attack on a rebel camp inside Ecuador on March 1 proves to have killed an Ecuadorian.

    "It would be extremely grave if it is proven that an Ecuadorian died," Correa said on a radio program. "We will not let this murder go unpunished."

    Ecuador broke off diplomatic ties with Colombia after Colombian troops entered the Ecuadorian territory to attack guerillas of the Revolutionary Armed Forces of Colombia (FARC), calling the raid a violation of its territorial sovereignty.

    The conflict briefly aroused fears of war in the Andean region as Ecuador and Venezuela ordered troops to their borders with Colombia.

    Then, at a Rio Group Summit on March 7, Colombian President Alvaro Uribe apologized to Correa and promised to abstain from similar raids in the future if his neighbors cooperate in the fight against FARC, resulting in a handshakes between the two and a crisis-over declaration from Correa.

    However, after Correa heard claims that an Ecuadorian locksmith might be among the 20 dead people killed in the Colombian attack, he ordered investigations and vowed to punish his neighbor if the claim proved true.