Police swarmed around CNN reporter Wolf Blitzer's home this weekend, responding to what turned out to be another example of the prank known as swatting. According to The Washington Post, someone sent a message to the police on Saturday evening, saying that someone had been shot at Blitzer's house in Bethesda, Maryland. After setting up a perimeter, though, police confirmed with CNN that Blitzer hadn't called in a shooting, and in fact wasn't even in town. Instead, says Montgomery Police Captain Paul Starks, someone had sent a fake message with Blitzer's address through a cell carrier's emergency relay system.

Swatting — a dangerous trick in which someone makes a fake 911 call, sending a SWAT team to investigate a shooting or suicide at the target's house — isn't a new trick, but a wave of high-profile incidents have drawn attention. Chris Brown, Clint Eastwood, Justin Timberlake, and other celebrities have been targeted in the past months. Security journalist Brian Krebs received the same treatment in March, possibly in retaliation for writing about a Russian site that sold sensitive data like social security numbers and addresses for famous figures.

Swatters can either use disposable phone numbers or place messages through emergency relay systems designed for the deaf, effectively masking their identity. In Blitzer's case, Starks appears doubtful that the culprit will be caught any time soon. "We don't know where these people are," he says. "They could be in New Zealand." However, some swatters have been found out — and have faced multi-year jail sentences for their fake calls. Many of these pranks are random, but Blitzer and CNN have also received intense public scrutiny in the wake of the Boston Marathon bombings, during which the network incorrectly reported that a suspect had been arrested.