Long-standing tensions between Morocco and Algeria have moved up a notch with a deadly confrontation at sea last week between the Algerian Coast Guard and several men on water scooters.

Algeria’s Defense Ministry has acknowledged that its forces fired on a group of people on water scooters who strayed into Algerian waters from Morocco last Tuesday, and that a body was later found. The shooting has provoked national anger in Morocco.

On Monday, Morocco’s National Council for Human Rights strongly condemned the Algerian Coast Guard’s use of live ammunition against unarmed civilians, decrying the incident as a “severe violation of international standards and human rights laws.”

Separately on Monday, several dozen Moroccan human rights activists gathered outside the country’s parliament headquarters in Rabat, denouncing “the Algerian military regime” and brandishing signs demanding accountability for the incident.

The North African neighbors have no diplomatic relations and their maritime border has been closed since the 1990s because of long-running disputes, mainly over the territory of Western Sahara. But deadly confrontations at sea are unusual.

Moroccan media contend that Algerian forces killed two vacationers in the incident last week. France says a French citizen was among those killed and another French citizen was detained.

The Algerian Defense Ministry said in a statement late Sunday that coast guard units had intercepted three water scooters that had clandestinely entered Algerian waters.

“Given the increased activity of drug trafficking gangs and organized crime in this maritime border region and the obstinacy of those riding the water scooters, coast guard personnel fired warning shots. After several attempts, shots were fired, forcing one of the water scooters to stop, while the other two fled,’’ the statement said.

The next day, an Algerian coast guard patrol recovered the body of a man with a bullet hole from a firearm, the statement said, without elaborating. Moroccan forces recovered another body, according to Moroccan media reports.

One of the men on the water scooters, Mohamed Kissi, told Moroccan news website 360.ma that he, his brother Bilal and friends were on vacation and riding personal watercraft off the coast of the Moroccan town of Saaidia when they ran low on gas and drifted into Algerian territory. His brother was killed and was buried in the area last week. The family of the other person killed is seeking repatriation of his body from the Algerian forces, according to Moroccan media reports.

Moroccan officials have not provided details about what happened.

Moroccan prosecutors opened an investigation into a “violent sea incident” involving five people on water scooters, the official Moroccan news agency MAP reported.

Moroccan human rights protesters envision tougher action. Idris Sedrouai, president of the Moroccan Association for Citizenship and Human Rights, speaking at the protest, characterized the incident as a “deliberate and premeditated assassination.”

Sedrouai said his association, along with other like-minded organizations, is studying the possibility of filing a lawsuit in international courts against the leaders of the Algerian Army.