The U.S. Embassy in Tokyo has received a threat via the Internet about a possible bomb attack this week, although it has yet to determine its credibility, the embassy said in an e-mail message sent Monday to American citizens living in Japan.

In the e-mail notice sent to registered American residents in Japan, the embassy said, "The U.S. mission in Tokyo has received information, through the Internet, about a possible bomb attack against the American Embassy during the week of May 10."

The e-mail said the embassy has notified the appropriate Japanese authorities.