Three were arrested and one is being sought in an alleged plot to blow up the jet fuel line at JFK Airport in New York City. Here are other recent alleged homegrown terrorism plots targeting high-profile American landmarks:

June 2006: Seven men were arrested in what officials called the early stages of a plot to blow up the Sears Tower in Chicago and destroy FBI offices and other buildings.

July 2006: Authorities broke up a plot to bomb underwater New York City train tunnels to flood lower Manhattan.

May 2007: Six people were arrested a month ago in an alleged plot to unleash a bloody rampage on Fort Dix in New Jersey.