Iran's bloody crackdown on nationwide protests killed at least 6,126 people while many others still are feared dead, activists said Tuesday, as a U.S. aircraft carrier group arrived in the Mideast to lead any American military response to the crisis.

NATO Secretary-General Mark Rutte insisted Monday that Europe is incapable of defending itself without U.S. military support and would have to more than double current military spending targets to be able to do so.