Social Security numbers and other personal information from more than 2,000 University of California applicants may have been seen by other students because of a problem with an application status Web site.

So far, UC knows of only 108 students among nearly 99,000 applicants who had personal information displayed to other students. Letters notifying them of the lapse were sent out Thursday. Now UC is mailing letters to an additional 2,048 whose information may have been displayed to other applicants.

Officials say they are working to determine if even more students may have been affected and will contact them if personal information was revealed.

Although no financial information or admission decisions was shown, students were able to see such things as other applicants' names, phone numbers, Social Security numbers, birth dates, citizenship status and test scores. The problem was discovered after a student who logged on using a user ID and password saw personal information about another student and called to let that student know. On March 1, a parent reported the problem to ETS, which operates the web site for UC, and it was immediately taken down, said UC spokeswoman Lavonne Luquis.

The problem does not involve the Web site where students apply or find out if they were admitted.

Luquis said officials still are investigating what caused the problem. The letters refer families to Web sites and telephone numbers to get information about identify theft and fraud, though Luquis said there is no indication any of the information has been misused.

``We are very distressed about this situation and hope students will accept our apologies for any concern it may cause them,'' Dennis Galligani, associate vice president for student academic services, said in a statement.

Families seeking information about whether their student may be affected can call (800) 523-2048 in California or (925) 808-2181 outside California.