BRUSSELS - NATO demanded an immediate halt to "aggressive acts" against alliance member Turkey on Wednesday after a mortar strike from Syria killed five Turkish civilians.

The shelling "constitutes a cause of greatest concern for, and is strongly condemned by, all allies", NATO ambassadors said in a statement, after they held a rare late-night meeting at Turkey's request to discuss the incident.

"The alliance continues to stand by Turkey and demands the immediate cessation of such aggressive acts against an ally, and urges the Syrian regime to put an end to flagrant violations of international law," the statement said.

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