Terrorism incidents may be at the highest point in 20 years.

The State Department is scrambling to revise its annual report on global terrorism to acknowledge that it understated the number of deadly attacks in 2003, amid charges that the document is inaccurate and was politically manipulated by the Bush administration.

When the most recent "Patterns of Global Terrorism" report was issued April 29, senior Bush administration officials immediately hailed it as objective proof that they were winning the war on terrorism. The report is considered the authoritative yardstick of the prevalence of terrorist activity around the world.

"Indeed, you will find in these pages clear evidence that we are prevailing in the fight" against global terrorism, Deputy Secretary of State Richard L. Armitage said during a celebratory rollout of the report.

But on Tuesday, State Department officials said they underreported the number of terrorist attacks in the tally for 2003, and added that they expected to release an updated version soon.

Several U.S. officials and terrorism experts familiar with that revision effort said the new report will show that the number of significant terrorist incidents increased last year, perhaps to its highest level in 20 years.