From [1] CNN, with thanks to Jeffrey Imm:

WASHINGTON (CNN) -- The United States warned Americans in the Gulf state of Qatar Friday to avoid major hotels in Doha over the next week due to the possibility of a terrorist attack.

"The embassy advises Americans to continue to avoid major hotels in Doha during the upcoming week. The embassy is not at this time recommending that Americans defer travel to Doha," the U.S. Embassy in Qatar said in a message to Americans.

It said Qatari security services were aware of the threat and taking measures in response.