Iranian media on Saturday reported several explosions near the country's major oil hub of Kharg Island in the Gulf, days after renewed fighting broke out with the United States.
Fars news agency said blasts were heard by its correspondent but that there was no smoke visible, while the SNN news agency claimed "an Iranian tanker was targeted by the US" near the island.
There was no immediate comment from US or Iranian officials.
Fighting between the foes resumed last Sunday with US attacks on Iran as their war passed its six-month mark.
The American strikes prompted retaliatory attacks by Tehran on US targets in West Asia.
Iran said Thursday that its armed forces had hit US military bases in Kuwait and the United Arab Emirates, vowing to avenge civilian deaths at a wedding that it blamed on Washington.
The two sides also remain vying for control of the strategic Strait of Hormuz, with Iran blocking the passage of ships as Washington maintains a counter-blockade of Iranian ports.