Seven people were arrested Thursday in connection with the early stages of a plot to attack Chicago's Sears Tower and other buildings in the U.S., a federal law enforcement official said. The official told The Associated Press the alleged plotters were mainly Americans with no apparent ties to al-Qaida or other foreign terrorist organizations. He spoke on condition of anonymity so as not to pre-empt news conferences planned for Friday in Washington and Miami. Miami U.S. Attorney R. Alexander Acosta said in a statement that the investigation was an ongoing operation and that more details would be released Friday. Local...