BOTHELL, Wash. — A father's decision to install a Web camera at home paid off when his son, logging on from Washington, D.C., spotted an intruder and alerted authorities who made an arrest.

Snohomish County sheriff's deputies said the father installed the camera because he suspected someone had been in the house in the suburbs northeast of Seattle while the family was away.

"I've never heard of anything like this," sheriff's spokeswoman Jan Jorgensen said. "I think it's really cool they set this thing up when they had concerns."

Last Friday the 18-year-old son logged on and saw images of a neighbor, also 18, who was supposed to be looking after the family's cats but had been told to stay out of the house.

Soon afterward, Jorgensen said, deputies pressed the house intercom button and said, "Come out with your hands up."

Getting no response, deputies began a search and found the intruder lying in the shower.