At least 19 people are dead after a shootout between Russian troops and Islamist militants rocked Grozny, capital of the troubled Russian province of Chechnya.
The teen girls from Colorado were stopped in Germany on their way to Syria to join militant groups, including ISIS, according to the FBI.
The conflict against ISIS militants is in danger of spilling into Turkey.
The White House announced the troop deployment Tuesday following the beheading of a second American journalist, Steven Sotloff. The new personnel will be part of a now 820-person force providing U.S. diplomatic security.
The advisers reportedly will plan for the evacuation of refugees that have been stranded as ISIS militants advance in the region.
Medyan Dairieh, a reporter for VICE News, recently spent three weeks embedded with the terror group known as the Islamic State of Iraq and Syria.
The feared Islamic insurgents have opened an office where single women can register to marry fighters from the extremist organization, according to unconfirmed reports.
The militant group has been destroying holy sites as it seeks to impose Sharia law. This week, it blew up the tomb of the biblical prophet said to have survived inside a whale.
The insurgents reportedly took uranium compounds from Mosul University. The material could potentially be used for manufacturing weapons of mass destruction.
Militants from the Islamic State in Iraq and Syria said on Twitter that they had executed 1,700 Iraqi government soldiers, The New York Times reports. On Sunday, a string of bombs went off, killing 15 and wounding over 30.