Two ships sank in, or near, the Strait of Hormuz on Wednesday after suffering attacks from as-yet unidentified “projectiles.”

The general presumption is that Iran attacked the civilian vessels with missiles or drones and Iran claimed on Wednesday that one of the ships sank after hitting a mine laid in the strait by the Islamic Revolutionary Guard Corps (IRGC).

The Singapore-flagged container ship GFS Pride “sustained damage and a fire on board” while passing through the Strait of Hormuz on Tuesday, and “has since sunk,” according to a statement from the Maritime and Port Authority of Singapore (MPA) on Wednesday.

“MPA is deeply concerned about the continued attacks on ‌commercial shipping ⁠in the Strait of Hormuz. Such attacks are unprovoked, unjustifiable, and a breach of international law,” the MPA said.

The MPA said all 21 members of the crew were “safely evacuated,” and none were injured.

Meanwhile, the Cape Dao, a dry bulk carrier flagged to Antigua and Barbuda, succumbed to damage sustained from an attack on September 23 and sank near the Strait of Hormuz. The ship was left burning and adrift after the attack, which killed one member of its crew.

EuroNews on Thursday reported social media videos that “appeared to show cargo including mobile phones and luxury goods floating in the water near the Strait of Hormuz, with people in small boats collecting items.” This was presumably cargo left behind by the sinking Cape Dao.

Pride and Cape Dao were the second and third ships to be sunk by Iranian terrorism since the conflict between the U.S. and Iran began at the end of February.

The first was a Malta-flagged container ship called Safeen Prestige, which was hit by a missile in the Strait of Hormuz on March 4 and abandoned. When a tugboat flagged to the United Arab Emirates (UAE) named Mussafah 2 moved to assist on March 6, it was also hit by Iranian missiles. The Safeen Prestige finally succumbed to the fires raging on board and sank off the coast of Oman, on or about April 1.

The IRGC said on Thursday that a cargo ship struck a “naval mine” while using an “unauthorized route” through the Strait of Hormuz. The statement was accompanied by photos of a cargo ship that was sinking from its stern, dropping dozens of containers into the water, while a plume of smoke rose from its decks.

The United Kingdom Maritime Trade Operations (UKMTO) center said two unnamed container ships were struck by “unknown projectiles” while passing through the Strait of Hormuz on Tuesday evening, but both were able to continue after taking only minor damage.

Iranian state media on Thursday reported that an oil tanker caught fire while passing through a “prohibited zone” in the Strait of Hormuz with its tracking systems turned off. The report claimed Iranian forces were “monitoring” the ship, without taking credit for attacking it.

Two senior Iranian officials told Reuters on Wednesday that Iran is using “new tactics” to attack civilian vessels in the Strait of Hormuz, with the goal of keeping oil prices high to hurt President Donald Trump and his party in the midterm elections.

The officials said the “new tactics” went into effect about ten days ago and have resulted in a surge of ships suffering damage as they attempt to transit the strait. A U.S. military official told Reuters one of these tactics appeared to involve using small spotter boats to target ships, instead of relying on the radar installations that were largely destroyed by American airstrikes. U.S. forces destroyed at least one of these spotter boats last week.

UKMTO and maritime tracking services said the Iranians also appear to be expanding their targeting area beyond the Strait of Hormuz, to include the waters of Oman and the UAE. The Iranian officials predicted Iran’s terrorist attacks would completely shut down the strait before the U.S. elections in November.

“Just when they think they are getting close to the point where prices will fall, we will push them away from it. This is a game of chess. Such vessels would be safe nowhere, even outside the Strait of Hormuz,” one of the Iranian officials said.