The Algerian authorities have said a group of tourists who strayed into their waters from Morocco on jet skis were warned before they were shot at.
Two men were killed last week after an altercation with the Algerian coastguard.
In its first comment on the incident, the Algerian defence ministry said on Sunday that the tourists defied an order to stop “several times”.
However, a survivor has disputed this – saying they were never cautioned.
“I only heard gunshots directly that killed my brother Bilal,” Mohamed Kissim told the Reuters news agency.