Two Iranian military bases were struck by the US on Wednesday morning, Iran's semi-official Fars News Agency cited an official Iranian source as saying.
Earlier, US Central Command (CENTCOM) confirmed that the United States had struck southern Iran on Qeshm Island, in Bandar Abbas, and in Sirik overnight.
Iranian state media reported several injuries after US forces began launching what CENTCOM described as "a series of powerful strikes against Iran to impose heavy costs for targeting and attacking commercial shipping crewed by innocent civilians in an international waterway."
Later, Iran's Revolutionary Guards claimed they targeted 85 US military sites in Bahrain and Kuwait, "in response to US ceasefire violations," shortly after Kuwait's military reported sirens due to hostile missile and drone attacks.
Fars reported 10 explosions in Sirik and four in Mesen on Qeshm Island.
Fars also cited an Iranian military spokesperson, who announced that Iran would retaliate against the origin point of any strikes made against it.
"All of the American bases in the region are legitimate targets for our military drones," the army source stated.
One US official told Reuters that the strikes targeted Iranian air defense systems, coastal surveillance, surface-to-air missiles, anti-ship cruise missiles, and drone launch sites.
The strikes on Wednesday were four or five times bigger in scope and power than the strikes 10 days ago, another US official told Axios.
US revokes license authorizing Iranian oil sales
The Iranian Foreign Ministry condemned a US Treasury move to revoke the temporary suspension of sanctions on Iranian oil sales, saying that Iran "holds the United States responsible for violating the memorandum of understanding, and will take any measures we deem necessary to safeguard our interests and national security."
Iran's foreign ministry added that "The US has repeatedly violated the terms of the memorandum of understanding over the past 20 days, either directly or through the actions of the Zionist entity against Lebanon."
On Tuesday, the US revoked a general license that authorized the sale of Iranian oil, as a US official warned that Iran's actions in the Strait of Hormuz were "wholly unacceptable."
A source with knowledge of the attacks told The Jerusalem Post that Iran was responsible for launching at least five drones and missiles at three ships in the strait over the past day.
The US move came after three tankers reported being struck by unknown projectiles in and near the Strait of Hormuz in recent days, the British navy-affiliated agency UKMTO said in a report.
There was no immediate comment from Tehran or any claim of responsibility.