The US military has released a video which it says shows Iranian special forces removing an unexploded mine from the side of an oil tanker damaged in an attack in the Gulf of Oman on Thursday.
The US also released images of the Japanese tanker apparently showing the unexploded mine before it was removed.
A Norwegian tanker in the gulf also reported being hit by three blasts.
The US accused Iran of being behind the attacks. Iran said it "categorically" rejected the allegation.
The blasts came a month after four oil tankers were damaged in an attack off the coast of the United Arab Emirates. The US blamed Iran for that attac