Thailand, Malaysia, Indonesia and Tanzania are among countries cited by the State Department in travel advisories warning of the increased threat of possible terrorist actions against Americans as a result of the Persian Gulf war.

Thailand. A credible threat to American and other foreign organizations was received in Bangkok.Indonesia. An explosive device was found Jan. 18 in the American ambassador's residence in Jakarta.

Malaysia. A bomb was discovered on Jan. 25 in a ticket office in Kuala Lumpur. It was later detonated.

Tanzania. There has been a credible threat against American officials.

The inquiry number, (202) 647-5225, for the State Department's citizen emergency center, which lists current travel advisories, is now connected to 24 lines instead of the usual 18 because of the volume of calls. The department's crisis center, (202) 647-0900, with 55 lines, is handling advisory calls as well.