The governor's office will change the way mail is sorted and received after a suspicious letter with white powder was found yesterday by a clerk to Gov. Linda Lingle.

The powder was harmless, but it spurred a lockdown of the governor's office for more than an hour yesterday as hazardous materials teams tested the letter, spokesman Russell Pang said.

The governor was on Maui yesterday.

Governors across the country have received similar mail. Authorities said mail containing white powder has been received this week by governor's offices in Alabama, Alaska, Maine, Michigan, Minnesota, Mississippi, Missouri, Montana and Rhode Island.

Barry Fukunaga, Lingle's chief of staff, told reporters yesterday that letters to the governor are usually sorted in a mail room at the state Capitol building, then opened in the governor's offices.

In the wake of yesterday's incident, he said, that procedure will change so that mail is pre-screened outside of the governor's offices.

Pang said this is not the first time the governor's office has received suspicious mail.

Authorities warned the governor's office last week to be on the lookout for suspicious letters with a return address from San Antonio, Texas. About 10:30 a.m. yesterday, a clerk to the governor found a suspicious letter from San Antonio and called security, Pang said.

The letter was addressed to Lingle, he said.

Honolulu Fire Department hazardous materials teams responded, forcing a lockdown of the governor's office.

By noon, tests had found the white powder in the letter to be harmless and the governor's office was reopened.

HFD spokesman Capt. Terry Seelig said a test with a confidence rating of 98 percent indicated the substance inside the letter was cornstarch.

The substances found in the letters to other governors have also been harmless.

FBI spokesman Rich Kolko in Washington, D.C., said the Dallas FBI office is investigating the letters and has warned other states to be on the lookout for similar letters.