The United States is considering air strikes in Iraq in response to a militant surge in northern areas that has left minority groups trapped by fighting, a U.S. official told CNN.
The official said the possibility of such military action "has been something" the Obama administration "has been talking about for some time and the latest news just might meet the threshold for action."
Iraq's largest Christian town has been overrun by the same militant Islamists who have gained a foothold in parts of eastern Syria and western and northern Iraq.
The advance by ISIS, or the Islamic State, has caused thousands of Christians in the city to flee, just as other minority groups targeted by it have done.
ISIS seeks to create an Islamic caliphate that stretches from Syria to Iraq. It has aggressively targeted Iraqi minority religious groups.
The Obama administration is talking with officials in Baghdad and Erbil and is looking at options to provide humanitarian support, including but not limited to Iraqi government air drops, another U.S. official said.
White House spokesman Josh Earnest refused to offer any details on possible actions under consideration.
Asked specifically about possible air strikes, he said he was not in position to comment on that.
Noting Iraq has many problems, he described the current situation as "a particularly acute one" with "innocent populations persecuted just because of their ethnic identity," calling it "disturbing."
At the same time, Earnest repeated principles for any possible military involvement in Iraq previously stated by President Barack Obama, declaring no American military solution existed for Iraq and no U.S. ground troops would be sent there.
"We can't solve these problems for them. These problems can only be solved with Iraqi political solutions," he said.
A senior State Department official said the United States also is weighing opening a humanitarian corridor, providing support to Kurdish and Iraqi forces.
The United States has 245 military personnel in Iraq, 90 of whom are advisers. The carrier USS George H.W. Bush is also in the region as well as other Navy ships.