Facebook’s Zuckerberg Testifies, Arizona Plane Crash, Security Adviser Resigns, Police Perimeter Security Facebook’s Zuckerberg Testifies, Arizona Plane Crash, Security Adviser Resigns, and More 4/11/2018 by Mark Tarallo ASISSMArticleBodyUnder fire for the worst privacy episode in his company's history, Facebook CEO Mark Zuckerberg batted away often-aggressive questioning from U.S. federal lawmakers Tuesday at a Capitol Hill hearing. Several U.S. Senators accused Zuckerberg of failing to protect the personal information of millions of Americans from Russians intent on upsetting the U.S. election. During about five hours of Senate questioning Tuesday, Zuckerberg apologized several times for Facebook failures, disclosed that his company was "working with" special counsel Robert Mueller in the federal probe of Russian election interference, and said it was working hard to change its own operations after the harvesting of users' private data by a data-mining company affiliated with Donald Trump's campaign, the Associated Press reports. A small plane crash at the TPC Scottsdale Champions Course in central Arizona Monday night has left six people dead, officials said. The plane departed Scottsdale Airport and crashed soon afterward at the golf course, just north of the airports. None of the six people aboard the Piper PA-24 survived, the Federal Aviation Administration said. Their names were not immediately released. The cause of the crash is under investigation by the National Transportation Safety Board, which arrived on site, ABC News reported. White House homeland security adviser Tom Bossert is leaving the Trump administration, The Washington Post reports. Bossert leaves one day after national security adviser John Bolton begins his the job. Bossert's resignation was requested by Bolton, according to two people familiar with the situation who requested anonymity to discuss internal personnel issues, the Post reports. So far this year, the president has changed his secretary of state, national security adviser, veterans affairs secretary, CIA director, chief economic adviser, staff secretary, communications director, and members of his legal team.Some police officers and city leaders in Dallas are pleased that perimeter fencing is finally being installed at some police substations, CBS Dallas/Fort Worth reports. Crews are putting up fencing at the department's northeast and south central substations. The $3 million project should be completed at all seven police substations by July. The added security measures come nearly three years after the Dallas Police headquarters building came under attack.