Al Gore to Campaign For Hillary Clinton, Police Officers Attacked in Brussels, Protests Over Land in Ethiopia: P.M. Links

• 

  Kier Duros/flickr

  Al Gore will reportedly be hitting the campaign trail for Hillary Clinton. A new Massachusetts poll shows William Weld just three points behind Elizabeth Warren in a hypothetical 2018 matchup. A float in a farmer's fair parade in Indiana depicted Donald Trump executing Clinton.

• The FBI secretly arrested a contractor at the National Security Agency several weeks ago on allegations of stealing classified codes.
• Relations between the U.S. and Russia are at their lowest point since the 1970s.
• Two police officers in Brussels were stabbed in what prosecutors say they have reason to believe was a "terrorist attack."
• Demonstrators in Ethiopia destroyed a foreign-owned textile company while protesting and rioting over land seizures.
• Hurricane Matthew could make landfall in Florida as early as Friday morning.
• Three chemists were awarded the Nobel Prize in chemistry for their work on molecular mechanics.