A U.S. official says the Embassy in Riyadh and two other diplomatic missions in Saudi Arabia will remain closed for consular services due to security concerns.

The diplomatic facilities in Riyadh, Jiddah and Dhahran have been closed since Sunday. A security message to U.S. citizens encouraged them to be aware of their surroundings, avoid large gatherings and keep a low profile.

In an email to The Associated Press Thursday, an embassy spokesman said officials will continue to assess and coordinate with Saudi authorities and come to a decision "at the appropriate time" about when to resume consular services.

Last week, the embassy warned citizens that individuals associated with a terrorist organization could be targeting U.S. citizens working for oil companies in the Eastern Province.