The US military has unleashed a new wave of strikes against Iran on Tuesday and revoked a license allowing the country to sell oil after three tankers were hit by projectiles in the Strait of Hormuz.
US Central Command said it hit over 80 targets in a series of strikes intended to impose what it called heavy costs.
The military command said it struck more than 60 small boats of the Islamic Revolutionary Guard Corps in an effort to degrade Iran's ability to attack commercial shipping.
"The unwarranted aggression by Iranian forces is a clear and dangerous violation of the ceasefire and undermines freedom of navigation," CENTCOM said in a statement.
Iranian media reported explosions early Wednesday local time on Iran's main oil hub of Kharg Island, on Qeshm Island, and in the southern port cities of Sirik and Bandar Abbas.
No civilian deaths were reported, but several people were injured by shrapnel from an "enemy projectile" that hit a commercial pier in Sirik, according to an Iranian state TV reporter.
The reports said strikes also hit fishing piers in Sirik and in Bandar Abbas, where several fishing boats were set ablaze.
Iran's Press TV said several blasts were heard on Kharg Island in southern Iran. The report did not provide details on the cause of the explosions, possible damage or casualties.
The CENTCOM statement made no mention of Kharg Island, from which Iran exports 90 per cent of its crude oil. The island was last attacked by the US in April.
A US official told Reuters that strikes targeted Iranian air defense systems, coastal surveillance systems, surface-to-air missiles, anti-ship cruise missiles, and drone launch sites.
The incidents were only the latest threat to the ceasefire agreement the US and Iran struck last month, pausing the conflict that started in February with US and Israeli strikes across the Islamic Republic.
In a potentially major blow to that agreement, Washington moved on Tuesday to withdraw a key concession that had allowed Iran to sell oil on international markets.
Oil prices rose more than 3 per cent after the US announced the move.
Under the interim US-Iran agreement, the US Treasury issued a June 22 general license to allow the sale of crude oil and petrochemical and petroleum products of Iranian origin through August 21. In revoking that license on Tuesday, it gave Iran until July 17 to wind down any transactions.

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