(CNN) Yemen's Houthi rebels have attacked Saudi Arabia's oil facilities with drones, the Houthi-run Al-Masirah news agency said Saturday.

A Yemen armed forces spokesman was quoted by the agency as saying the Houthis successfully carried out a "large-scale" operation with 10 drones targeting Saudi Aramco oil facilities in Abqaiq and Khurais.

But preliminary indications are that the attacks Saturday that disrupted about half of the kingdom's oil capacity did not originate from Yemen and likely originated from Iraq, according to a source with knowledge of the incident. The same official said the damage was caused by an armed drone attack.

CNN National Security Analyst Peter Bergen said there have been more than 200 drone attacks launched by Houthi rebels from Yemen into Saudi Arabia, and none have been as effective as Saturday's attack, lending credence to the belief that the attack did not originate from Yemen.

The Saudi interior ministry said the drone attacks caused fires at two facilities of the state-owned oil company. In a statement posted on Twitter, the ministry said the fires were under control and that authorities are still investigating the incident.