In 1996, the internet-based service America Online had gained five million subscribers, all of whom were greeted with a news flash that read, "Government source reveals signs of life on Jupiter," when they logged onto the service on April 1. This headline was backed up by statements from a planetary biologist and an assertion by Ted Leonsis, AOL's president, that his company was in possession of documents that proved the government was hiding the existence of life on the massive planet. The story quickly generated over 1300 messages on AOL, and hundreds of people called the Jet Propulsion Laboratory in Pasadena, California trying to obtain more details about the discovery. When it turned out to be a prank, many questioned whether the service had risked losing its credibility by perpetrating such a stunt, but AOL dismissed these concerns. A spokeswoman for the company later explained that the hoax had been intended as a tribute to Orson Welles' 1938 halloween broadcast of the "War of the Worlds."