A senior Iraqi Interior Ministry source believes a resistance 'splinter' group was responsible for the September 10 drone attack on Saudi Arabia's East-West oil pipeline, which originated from Iraqi territory. The incident has intensified pressure on Iraqi Prime Minister Ali al-Zaidi to bring armed groups under state control ahead of the US-led coalition's final withdrawal by September 30. Zaidi has responded by sacking the Maysan operations commander, ordering an investigation, and closing border crossings with Iran.