Sunni Muslim militants have cemented their grip on northern Iraq with support from local tribes.
The Al-Qaeda-inspired militants took control of Iraq's second largest city, Mosul, one month ago, and expanded their control in areas near the border with Syria.
The insurgents have unilaterally declared the establishment of an Islamic state straddling Iraq and Syria.
Many of Mosul's 2 million residents have fled to the Kurdish autonomous region in the north.
But quite a few residents remain in the city to support the militant group in protest against the government of Prime Minister Nuri al-Maliki, who favors Shia Muslims.
A man living in Mosul told NHK on the phone that Sunni extremists are not visible in the city, and that members of local tribes are on the streets instead to maintain security.
He said the situation is so stable that people can walk on the streets even at night.
The Iraqi government has deployed its troops around another rebel-controlled northern city -- Tikrit -- to launch a major assault against the insurgents and retake the city.
Analysts say, however, it is unlikely that government forces will be able to take back control of Mosul any time soon.
Jul. 10, 2014 - Updated 11:53 UTC