A US Reaper drone was shot down over Yemen in the days before a similar attempt to destroy an American surveillance aircraft over the Gulf of Oman, the critical shipping route in which several oil tankers were attacked last week, the US has said.
A statement from US Central Command said the MQ-9 or Reaper drone was destroyed over Yemen, likely by a Houthi surface-to-air missile, on June 6. “The altitude of the engagement indicated an improvement over previous Houthi capability, which we assess was enabled by Iranian assistance,” the command said.
The US believe the missile used was a SA-6, a Soviet era low-to-medium-altitude surface-to-air missile system in use since the 1960s.
Shortly afterwards on June 13, a modified Iranian SA-7 surface-to-air missile attempted to shoot down a second US Reaper drone over the Gulf of Oman, Centcom said. An SA-7 is a shoulder-fired, low-altitude missile system with infrared homing guidance.
"Subsequent analysis indicates that this was a likely attempt to shoot down or otherwise disrupt the MQ-9 surveillance of the IRGC attack on the M/T [motor tanker] Kokuka Courageous."
The Kokuka Courageous, a Japanese tanker, was struck by an explosion in the Gulf on Thursday.
US Secretary of State Mike Pompeo has accused Iran's Islamic Revolutionary Guard Corps of carrying out the attack.
According to Centcom, the drone was flying over the Gulf to observe the Norwegian-owned Front Altair tanker, which was earlier attacked and was on fire.
The attempt to shoot down the US drone over the Gulf of Oman failed. “Its closest point of approach to the MQ-9 was approximately one kilometre,” Centcom said.
The US has released footage that it said showed members of the IRGC removing an unexploded limpet mine from the hull of the Japanese tanker.
Iran has previously threatened to block the Strait of Hormuz in protest against US policies, in a move that would severely disrupt the movement of oil supplies around the world.
The attacks sent crude prices soaring and the UAE and Saudi Arabia called on the international community to secure access to oil supplies.
Mr Pompeo, who led the CIA before becoming secretary of state, promised to provide further evidence of Iran's role in the attacks.
"The intelligence community has lots of data, lots of evidence," he said. "The world will come to see much of it."
Last week's attacks followed attacks on four tankers – two Saudi, one Norwegian and one Emirati – off the coast of Fujairah, in the UAE, on May 12.
An investigation by the three countries blamed those attacks on a state actor. The US has held Iran responsible for both sets of attacks.