The news that the alleged killer of a local radio reporter met his victim on a Web site for posting classifieds is rehashing a central question: How do you protect yourself online?

Authorities say 16-year-old John Katehis confessed to killing veteran radio newsman George Weber after they met on Craigslist and Weber invited him to his Carroll Gardens home.

Craigslist provides its users tips for safeguarding themselves before a face-to-face encounter. The Web site recommends insisting on a public place for the first meeting, telling a friend the location of the meeting and having a cell phone on hand at all times.

"You have to be careful," says Heide Langeneckert, who uses Craigslist. "Know what to look for and look a little closer at people."