The Liberian-flagged oil and chemical tanker, which was sitting idle, was attacked on Saturday about 140 miles west of the Republic of Congo's Port Pointe-Noire.
All 16 crew members sought refuge in a safe room onboard the Monjasa Reformer vessel, the spokesperson said.
The vessel is operated by Dubai-based Montec Ship Management, which is owned by Monjasa.
Montec reported the incident to a maritime cooperation centre operated by the British and French navies to maintain safety in the Gulf of Guinea.
The operator is working with all relevant maritime authorities in the region, including several navies, according to Monjasa.
The Gulf of Guinea has become a global piracy hotspot in recent years although cases have fallen there since 2021 as national authorities stepped up security efforts aided by foreign naval ships, according to the U.N. Security Council.
