Unexploded limpet mine removed from M/T Kokuka Courageous in the Gulf of Oman (CENTCOM)

WASHINGTON — In an effort to bolster its public case against Iran, the Pentagon on Monday released new photos that officials said show that members of Tehran’s Revolutionary Guard were responsible for attacks last week on two oil tankers near the Persian Gulf.

The images, many taken from a Navy helicopter, show what the Pentagon said were Iranian forces removing an unexploded mine from the side of the Japanese-owned Kokuka Courageous oil tanker in the Gulf of Oman.

Officials last week said the move appeared to be an attempt to remove forensic evidence from the scene of the attack. But it's not clear if examination of the mine would have made it definitively clear that the device was planted by the IRGC.

This image released by the U.S. Department of Defense on Monday, June 17, 2019, is a view of hull penetration/blast damage on the starboard side of the motor vessel M/T Kokuka Courageous, which the Navy says was sustained from a limpet mine attack while operating in the Gulf of Oman, on June 13th. (U.S. Department of Defense via AP)
This image released by the U.S. Department of Defense on Monday, June 17, 2019, is a view of hull penetration/blast damage on the starboard side of the motor vessel M/T Kokuka Courageous, which the Navy says was sustained from a limpet mine attack while operating in the Gulf of Oman, on June 13th. (U.S. Department of Defense via AP)

Other photos show a large hole on the side of the Courageous, above the water line, that officials say appears to have been caused by another similar mine.

The release of the photos came as the U.S. works this week to convince members of Congress and allies that the accusations against Tehran are true. Iran has denied involvement in the tanker attacks and has accused America of promoting an "Iranophobic" campaign. Tehran, however, has repeatedly threatened to close the vital Strait of Hormuz, through which 20% of the world's oil flows.

U.S. officials say the Pentagon is sending about 1,000 additional American troops to the Middle East, as commanders try to bolster security for forces and allies in the region from what authorities say is a growing threat from Iran.

Officials say the deployment includes security forces and troops for additional surveillance and intelligence gathering in the region.

The troops are part of a broader military package of options that were initially laid out to U.S. leaders late last month, totaling as much as 10,000 forces, Patriot missile batteries, aircraft and ships.

This is the view of the remnants of a removed limpet mine’s placement, location, and damage sustained from a limpet mine attack, on the starboard side of motor vessel M/T Kokuka Courageous, while operating in the Gulf of Oman, June 13. A limpet mine is attached to a vessel via magnet and/or nails. The holes seen were created by nails used to hold the mine in place. (CENTCOM)
This is the view of the remnants of a removed limpet mine’s placement, location, and damage sustained from a limpet mine attack, on the starboard side of motor vessel M/T Kokuka Courageous, while operating in the Gulf of Oman, June 13. A limpet mine is attached to a vessel via magnet and/or nails. The holes seen were created by nails used to hold the mine in place. (CENTCOM)

The latest decision comes as Secretary of State Mike Pompeo and other top officials reach out to leaders in Asia and Europe to convince them that Iran was behind alleged attacks on shipping along a Middle East oil route.

Pompeo is expected to travel to Tampa, Florida, to meet with CENTCOM commander Marine Gen. Kenneth McKenzie Jr. and Army Gen. Richard Clarke, who is in charge of U.S. Special Operations Command; both commands have headquarters at MacDill Air Force Base.

Relations between the U.S. and Iran have deteriorated in recent months, as the Trump administration restored crippling sanctions and designated the Revolutionary Guard as a foreign terrorist organization.

Imagery taken from a U.S. Navy MH-60R helicopter of blast damage to M/T Kokuka Courageous. M/V Kokuka Courageous received damage consistent with a limpet mine attack in the Gulf of Oman, June 13.
Imagery taken from a U.S. Navy MH-60R helicopter of blast damage to M/T Kokuka Courageous. M/V Kokuka Courageous received damage consistent with a limpet mine attack in the Gulf of Oman, June 13.

That increased pressure preceded a string of attacks that the U.S. has blamed on Iran. In late May, four oil tankers off the coast of the United Arab Emirates were attacked with what appeared to be mines, and there was a rocket attack in Baghdad. Last week, similar attacks were launched against the Courageous and the Norwegian-owned MT Front Altair in the Gulf of Oman.

The U.S. military has also accused Iranian Revolutionary Guard troops of trying but failing to shoot down a U.S. drone to disrupt surveillance of the tankers during the attacks.

Imagery taken from a U.S. Navy MH-60R helicopter of the Islamic Revolutionary Guard Corps Navy after removing an unexploded limpet mine from the M/T Kokuka Courageous (CENTCOM)
Imagery taken from a U.S. Navy MH-60R helicopter of the Islamic Revolutionary Guard Corps Navy after removing an unexploded limpet mine from the M/T Kokuka Courageous (CENTCOM)