Nearly 1,900 holders of Hawai'i commercial driver's licenses are being warned to take measures to prevent identity theft after a state computer containing personal information was stolen three weeks ago.

The state Department of Transportation sent a letter Monday to the affected commercial driver's license holders to notify them of the security breach. The laptop computer contained the names, addresses, Social Security numbers and other personal information of 1,892 commercial vehicle license drivers.

Statewide, there are about 30,000 people with commercial driver's licenses, said Tammy Mori, department spokeswoman.

The laptop was assigned to a Transportation Department motor vehicle safety officer in charge of inspecting vehicles on O'ahu and was taken March 18 from a fifth-floor state office in the Kakuhihewa Building in Kapolei. The inspector said he left the computer unattended about 9:30 a.m. and that when he went to get it half an hour later it was gone, the Transportation Department said.

The incident was reported to police. No arrest had been made as of yesterday.

Although the theft occurred on March 18, the state did not notify the affected drivers until Monday. Mori said the department needed to follow protocol before sending the letters.

"We had to find out exactly what was on the laptop and identify all of the names, get their addresses, work with attorney general's office and police department, post notices all over our building to ensure that it wasn't just missing internally," Mori said. "So we went through all of the proper procedures before we moved forward with this."

Brennon Morioka, Transportation Department director, apologized for the incident and the "very serious impact the missing information could have on so many individuals."

He said his office is working with police and the attorney general to ensure that measures are taken to protect the identities of the drivers involved.

Morioka said there have been no reports that the information has been used for illegal purposes.

"We have also launched an internal investigation and are changing the process in which sensitive information is stored on laptops to prevent an incident like this happening again," Morioka said.

The information in laptop computers allowed state motor vehicle carrier officers to conduct inspections in the field, the Department of Transportation said. That information no longer is stored in the laptops, the department said.

Information about this incident, as well as what can be done to protect identities, can be found on the Department of Transportation Web page, www.hawaii.gov/dot, or at the Department of Commerce and Consumer Affairs' Web site, www.hawaii.gov/dcca.

The public may also call the Motor Vehicle Safety Office at 692-7661 or the DCCA Consumer Resource Center at 587-3222.