Algeria, on Wednesday, blamed Morocco for the killing of three Algerians in the border area with Mauritania.
"On 1 November, three Algerians were assassinated in a barbaric attack when their trucks were bombed as they were travelling between Algeria's Ouargala province and Mauritania's Nouakchott," the presidency said in a statement, cited by the state news agency.
It, however, did not provide details about where exactly the three were killed.
The statement said "several factors" indicate that Moroccan forces were involved in the attack, saying that "sophisticated weaponry" was used in the incident.
The Algerian presidency vowed that the incident "will not go unpunished".
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There was no comment from the Moroccan authorities on the Algerian accusation.
Video and images of the burnt vehicles were circulated on social media by Algerian residents in Ouargala province, amid calls for an investigation into the attack.
The new development adds to simmering tensions between the two neighbours, which escalated on 24 August, when Algeria severed diplomatic relations with Morocco, accusing Rabat of having "hostile tendencies". Morocco, on its part, dismissed the Algerian charges.
Algeria-Morocco ties have been tense for decades, against the backdrop of the disputed Sahara region between Rabat and the Algeria-backed Polisario Front.