SALEM, Ore. (AP) - Governor Ted Kulongoski and Portland Mayor Tom Potter have announced that later this month Oregon will be part of the largest anti-terrorism exercise in the nation's history.

The exercise is called "TOPOFF" - short for top officials. It is the fourth in a series of exercises since 2000 - and the third since the terrorist attacks of September 2001.

The five-day exercise will start October 15 in Portland. It will involve more than 50 local, state and federal agencies and five counties - including Clark County in Washington state.