Mysterious attacks on tankers near the Strait of Hormuz, assaults on oil facilities and an airport in Saudi Arabia, and the downing of a US military drone by Iranian forces – these are just a few of the incidents that have ratcheted up tensions in the Gulf in recent weeks.
The series of events, which began in May, comes against the backdrop of an escalating crisis between the United States and Iran, triggered by US President Donald Trump’s decision on May 8 last year to withdraw from a multilateral deal on Tehran’s nuclear programme.
In the year since, the US has reimposed and tightened crippling sanctions on Iran.
Tehran is now threatening to resume higher uranium enrichment.
As fears grow of an open conflict between the US and Iran, here’s a look at the key events that have contributed to the crisis.
The next day, Iran says US troops serving in the wider Middle East from the Horn of Africa to Afghanistan are “terrorist” organisations.
On May 5, White House National Security Adviser John Bolton announces the Pentagon is sending an aircraft carrier and a bomber task force to the Middle East.
“The United States is not seeking war with the Iranian regime, but we are fully prepared to respond to any attack, whether by proxy, the Islamic Revolutionary Guard Corps, or regular Iranian forces,” he says.
On May 7, the US says it is deploying B-52 bombers, a Patriot missile battery and an amphibious assault ship in the region.
On May 8, on the anniversary of US’s exit from the Iran nuclear deal, Tehran says it is preparing to increase enriched uranium and heavy water production as part of its decision to stop some commitments made under the 2015 pact with major world powers.
On the same day, Trump announces new measures against Iran’s steel and mining sectors. They come in addition to punishing sanctions on Iran’s oil and banking sectors.
Washington has since hit Iran’s largest petrochemical group PGPIC with sanctions.
On May 12, four ships, including three oil tankers, are damaged in mysterious “sabotage attacks” off the United Arab Emirates.
Bolton says on May 30 that Iran is “almost certainly” behind the attacks.
On June 6, the UAE says the initial findings of a multinational investigation into the attacks point to the likelihood that a state was behind them, but does not blame any specific country.
On June 13, the day Japanese Prime Minister Shinzo Abe meets Iran’s Supreme Leader Ayatollah Ali Khamenei in Tehran, a Norwegian and a Japanese tanker come under “attack” in the Gulf of Oman. Washington, London and Riyadh blame Iran, which denies involvement.
Yemen’s Houthi rebels launch drone attacks on Saudi Arabia on May 14, striking a major oil pipeline and taking it out of service. Two days later, Riyadh, a key US ally, blames Iran for the drone attack on its pipeline.
The US and Saudi Arabia accuse Iran of arming the Houthis, but Tehran denies the claim.
Saudi Arabia’s King Salman hosts three high-level summits in Mecca on May 31 and June 1, drawing heads of state from across the Middle East and Muslim countries to present a unified Muslim and Arab position on Iran. The monarch calls on the international community to use all means to confront Iran and accuses Tehran of being behind “terrorist operations” that targeted Saudi oil interests.
On June 12, Riyadh says 26 people are wounded in an attack by Houthis targeting an airport in kingdom’s southwestern town of Abha. The Houthis claim they had launched a cruise missile at the airport.
A rocket lands near the US embassy in Baghdad on May 19. No one is harmed. It’s not clear who is behind the attack, but Trump tweets: “If Iran wants to fight, that will be the official end of Iran. Never threaten the United States again!”
Iran’s Foreign Minister Mohammad Javad Zarif responds by tweeting that Trump had been “goaded” into “genocidal taunts”.
On May 15, the US pulls out all non-essential staff from Iraq, citing threats to its forces in the country. A senior US military official blames Iranian proxies in Iraq for the rocket attack.
On June 16, CENTCOM says an Iranian missile tried to destroy a US drone on a surveillance mission. Washington says a US drone was shot down on June 6 with a missile fired from Yemen “that we assess had Iranian assistance”.
On June 17, Iran’s atomic energy organisation says Iran will surpass the uranium stockpile limit set under the 2015 nuclear deal from June 27.
On June 20, the IRGC says it shot down a US “spy drone” which violated Iranian airspace near the Strait of Hormuz, in “a clear message” that Tehran will defend its borders.
The US confirms the downing but says the drone was downed in international waters. Trump tells reporters at the White House that Iran “made a very big mistake” and the US “will not stand for it”.
Iran vows in response to go to the United Nations to prove Washington was “lying”.