The US did not immediately confirm the purported attack, which came a day after the US military said forces struck three Iranian oil tankers in response to a missile attack on Navy warships Iran says it struck an unmanned U.S. Key points and original sources are listed below.

• The US did not immediately confirm the purported attack, which came a day after the US military said forces struck three Iranian oil tankers in response to a missile attack on Navy warshipsS1

• Iran says it struck an unmanned U.S. vessel trying to enter the Strait of Hormuz, the latest salvo in a new flare-up of fighting between the two countries.S2