New Delhi, Oct. 12 -- Saudi Arabia has extended the closure of Riyadh's King Khalid International Airport until October 17 after deadly attacks blamed on Yemen's Houthi rebels disrupted flights and raised questions about the kingdom's ability to defend critical infrastructure.

The airport has been shut since Saturday's attack, which reportedly killed 13 people and wounded more than 300.

A further attack on Sunday killed one person and injured nearly a dozen others.

The strikes have highlighted the growing capabilities of the Houthis' missile and drone arsenal and the challenges facing Saudi Arabia despite its advanced air defence systems, as attacks reach deep inside Saudi territory.

The Houthis, an Iran-backed movement that seized Ye...