The New York Times says the drone came from Iraq, Britain's foreign secretary names the Houthis, Iraq's military names nobody

One report carries the closure. The New York Times is the only report we hold that mentions the pipeline: "A drone attack from Iraq forced Saudi Arabia to close its East-West pipeline, the kingdom said." It gives the attack an origin, not an author, and attributes the closure to the kingdom inside the sentence.

Who each account blames.

What is not settled. No report we hold names who launched the drone. None gives a casualty or damage figure. None says how much crude the line carries, or how long it stays shut, so the word "lifeline" in the one headline that uses it stands with no number behind it. No report links the alerts over the two towns to the pipeline. Nine of the 12 are single-sentence bulletins with no body text.

What this is about. A drone attack has shut, for now, one of the few routes Saudi Arabia has for getting its oil to buyers without sailing it past Iran. That is what the kingdom told The New York Times.

How it got here.

• The pipeline. Most Saudi oil comes out of the ground in the east, near the Persian Gulf. Tankers leave the Gulf through the Strait of Hormuz, a narrow channel next to Iran. In the early 1980s, during the Iran–Iraq war, the kingdom built the East–West pipeline. It carries crude across the country to Yanbu, a port on the Red Sea, so exports can avoid Hormuz.
• Why it matters now. The New York Times calls the line "a key workaround to Iran's Persian Gulf blockade". Anadolu Agency's own section headings name a "US-Iran war" and a "Hormuz crisis". The reports we hold do not say how either began.
• Yemen. The Houthis, an armed movement also called Ansar Allah, took Yemen's capital, Sanaa, in September 2014. In March 2015 a Saudi-led coalition went to war in support of Yemen's internationally recognised government. The Houthis are aligned with Iran. Earlier this month, reports we covered said the Houthis struck Saudi oil sites and took ground on Yemen's Red Sea coast. Anadolu reports they now claim districts near the Bab al-Mandab strait.

Who is involved, and why.

• Saudi Arabia. Its oil exports and its southern towns are exposed. Abha and Khamis Mushait, where the civil defence sounded alerts, lie in Asir province near the Yemeni border.
• Iraq. The kingdom says the drone came from Iraq. Armed groups aligned with Iran operate there. Iraq's government says it will stop attacks launched from its soil.
• Britain. Its foreign secretary, Ed Miliband, has backed Saudi Arabia and Yemen's government against the Houthis.

What is at stake. The pipeline's oil leaves by the Red Sea. It then has to pass the Bab al-Mandab, at the Red Sea's southern end, where the Houthis are fighting. If Hormuz is blocked, the pipeline is shut and that southern strait is contested, Saudi crude has no route out that nobody threatens.

Where it stands. No report we hold names who launched the drone. None says how long the line will stay closed.