A strike on Tuesday targeting a boat from the pro-Palestinian Sumud flotilla to Gaza that was moored near Tunis was "a premeditated aggression", the Tunisian interior ministry said.
Tunisian authorities had earlier denied that a similar incident the day before was an attack.
The Global Sumud Flotilla is an international civilian movement seeking to peacefully transport humanitarian aid to Gaza, to break the Israeli siege on the war-torn enclave through international waters.
It is currently located off the coast of Sidi Bou Said near the Tunisian capital, awaiting departure.
Earlier this week, the flotilla organisers reported that two of the boats were targeted by "drone attacks" - the Portuguese-flagged Family Boat on Monday evening and the British-flagged L’Alma on Tuesday evening. No injuries were reported.
