WASHINGTON (AP) — The United States is warning Americans traveling to Saudi Arabia about the risk of ballistic missile attacks from neighboring Yemen.

A new U.S. travel warning follows a Houthi missile attack in early November near the international airport in the Saudi capital, Riyadh. The missile was intercepted. Both the U.S. and Saudi Arabia say the Houthis got the missile from Iran. The Houthis are Shiite rebels who control much of Yemen.

The travel warning says several long-range missiles have been fired from Yemen at major cities in the last year. It also says terrorist attacks "can occur without warning anywhere" in Saudi Arabia.

The State Department also says that U.S. government workers and their families are prohibited from traveling to the areas of Qatif and Hofuf in Saudi Arabia.