The U.S. warned that terrorists could be planning to attack or kidnap American oil workers in Saudi Arabia, and said it is shutting down diplomatic services on Sunday and Monday because of “heightened security concerns.”

The U.S. embassy in Riyadh, the Saudi capital, on Saturday warned Americans to take extra precautions and limit non-essential travel.

A day earlier, the embassy said in a notice that it had information that “as of early March, individuals associated with a terrorist organization could be targeting Western oil workers, possibly to include those U.S. citizens working for oil companies in the Eastern Province, for an attack(s) and/or kidnapping(s).” The embassy said it had no knowledge of specific planned attacks.

The U.S. and other countries closed their embassies in the neighboring country of Yemen in February and urged their citizens to leave the country amid spiraling security fears over the collapse of the country's government.

IN-DEPTH

— Phil Helsel