U.S. Officials Say Iran Is Laying Mines in the Strait of Hormuz

Iran has begun laying mines in the Strait of Hormuz, the Persian Gulf channel that carries 20 percent of the world’s oil, according to U.S. officials, an effort that could further complicate American efforts to restart shipping there.

While the U.S. military said it had destroyed larger Iranian naval vessels that could be used to quickly lay mines in the strait, Iran began using smaller boats for the operation on Thursday, according to a U.S. official briefed on the intelligence.

Iran’s Islamic Revolutionary Guards Corps can deploy hundreds, even thousands, of the small boats, which the Iranian force has long used to harass larger ships, including the U.S. Navy’s.

Iran said it was closing the strait shortly after the United States and Israel began their attacks on Feb. 28, disrupting global shipping and sending oil prices up sharply and shaking the global economy. On March 2, a senior official with the Republican Guards announced that the strait was closed and claimed Iran would “set those ships ablaze,” according to state media.

Strikes have hit multiple vessels in the area since, some of which Iran claimed responsibility for. On Tuesday, an Iranian deputy foreign minister, Majid Takht-Ravanchi, denied that Iran was mining the strait.

In his first remarks since the war broke out, Iran’s new supreme leader, Mojtaba Khamenei, said in a written statement on Thursday that “the lever of blocking the Strait of Hormuz must continue to be used.”

The new mining effort is not particularly fast or efficient, the officials said, but the Iranians appear to be hoping that they can lay them faster than the United States can clear them and, therefore, create a further deterrent for ships to move through the strait.

Iranian activity in the strait has become a focus of U.S. military and intelligence agencies as the Trump administration looks for ways to keep oil commerce flowing.

President Trump has warned Iran against mining efforts. On Monday, he wrote in a social media post that the United States would hit Iran “twenty times harder” if it blocked oil flowing through the strait. On Tuesday, he warned in another post, “If Iran has put out any mines in the Hormuz Strait, and we have no reports of them doing so, we want them removed, IMMEDIATELY!”

The U.S. military said this week that it had attacked 16 Iranian mine-laying ships.

Mines in the Persian Gulf during the Iran-Iraq war in the 1980s heavily damaged commercial shipping. Today, with a fifth of the world’s oil passing through the Strait of Hormuz, the waterway is a critical choke point in global commerce.

But Iran has not needed mines to attack oil tankers and halt global shipping. On Wednesday, projectiles struck three more ships, drastically increasing fears that the war with Iran will curtail energy supplies.

CNN and CBS News have also reported recently on intelligence assessments about Iran’s efforts and intentions to place mines in the Persian Gulf.