President Donald Trump says the latest U.S. strikes hit Iran “very hard,” adding that the strikes were “in honor” of three American soldiers killed in recent days: two in Jordan and one in Iraq.

In the early hours of Monday local time, the US Central Command (Centcom) said it had launched a “new wave” of attacks for the ninth consecutive night as explosions were heard across Iran.

The United States said it had attacked military sites and communications networks to “further diminish” Tehran’s attacks on ships in the Strait of Hormuz.

Iran said it had responded with a “surprise attack” in Syria and targeted US planes at Jordan’s Aqaba airport.

Elsewhere in the region, Kuwait’s military said it had intercepted Iranian drones.

Regarding the US attacks, Iran’s semi-official Tasnim news agency reported that several cities had been attacked, including Tabriz, Chabahar, Konarak, Bandar Mahshahr and Bandar Imam Khomeini.

There were also reports from Iranian state media that two oil tankers had exploded as the ships attempted to cross the strait.

The Islamic Revolutionary Guard Corps (IRGC) said the tankers were passing through what it called an “unsafe and dangerous southern route” of the strait and “exploded and were detained.” Centcom disputed the claims.

The IRGC added that the strait “will not be safe for the transit of petrochemicals, not even a drop of oil and gas” as long as US attacks continue and that it will respond with a “punitive operation.”

Over the weekend, the United States confirmed that a service member had died following an Iranian attack in northern Iraq on Saturday.

That news came after the United States said that a separate attack on a base in Jordan on Friday had killed two soldiers there. The two have now been identified by the Pentagon as Private Isabella Gonzales, 19, and Lt. Tyler James Feehan, 25.

A third service member was declared missing after the attack in Jordan, and US officials say “unidentified remains” were found during the search process.

As attacks continued over the weekend between the United States and Iran, US Secretary of State Marco Rubio said the United States “always remains open to a diplomatic solution.”

He also said that “the world has to decide whether or not it is going to allow an international waterway to be under the control” of Iran, saying Tehran was using the crucial sea route as leverage.

His comments come as a preliminary agreement reached in mid-June to stop the fighting has collapsed, and negotiations for a permanent peace have made little progress after Trump declared the agreement was “over” on July 8.