HARRISBURG — State officials, citing privacy concerns, have taken down a Web site that allowed Pennsylvanians to fill out voter registration forms on their computers.

The site was shut down Tuesday night after officials learned that it was possible, by tampering with the coding, to use the site to view other people's registration information, including voters' driver's license numbers or the last four digits of their Social Security numbers.

The information "can be viewed, not changed," said Leslie Amoros, spokeswoman for the State Department, which oversees elections in Pennsylvania.