Kurdish forces have begun an operation to force out militants with the Islamic State group from a strategic town in northern Iraq.
Officials said Kurdish peshmerga fighters early Friday retook several areas of Jalawla, 115 kilometers northeast of Baghdad.
The flashpoint town, which is just south of the Kurdish semi-autonomous region, was captured by Islamic State extremists on August 11.
The peshmerga have recently begun regaining lost territory, in part with the help of U.S. airstrikes on Islamic State jihadists.
On Thursday, U.S. Defense Department chief Chuck Hagel said the threat posed by Islamic State extremists to global security is "beyond anything we have seen."
Hagel, speaking in Washington, described the militants as "more than a traditional terrorist group." He said it is better armed, trained and bankrolled than any previous militancy.
Hagel spoke alongside Joint Chiefs of Staff Chairman General Martin Dempsey, who described the Islamic State organization as having "an apocalyptic, end of days vision."
The general said the group can be defeated, but only if it is engaged in Syria as well as Iraq. He predicted the militancy will only be eradicated once it is rejected by the 20 million disenfranchised people living in the vast regions between Damascus and Baghdad.
Dempsey stopped short of predicting U.S. airstrikes in Syria where civil war has raged for more than three years, but said the presence of Islamic State militants in northern and western Iraq, and eastern Syria, must be addressed diplomatically, politically and militarily by the United States and its regional allies.
The general also voiced alarm about the growing evidence of European and some American fighters in the militant group. He said such recruits eventually could pose security threats when returning to their homelands.
Islamic State extremists, most of whom are Sunni Muslims, control a large swath of eastern Syria and northwestern Iraq. The group, accused of massacring religious minorities in northern Iraq, is actively seeking to establish a Sunni caliphate governed by strict Islamic law. It is actively recruiting other fighters to join the group.
Hagel also voiced regret over the recent failed attempt to rescue American journalist James Foley and others held captive by Islamic State.
A rescue mission authorized by President Barack Obama several weeks ago failed because the hostages were not at the location where they were believed to have been held.