Iraqi forces met heavy resistance Monday as they began the long-awaited campaign to liberate the city of Mosul from the Islamic State group, which has had two years to prepare for what is perhaps the most important siege in the war thus far.
"Day One has gone well," Pentagon spokesman Peter Cook said at a briefing Monday afternoon, adding that the Iraqi forces had exceeded their planned goal for what they hoped to accomplish on the first day of the battle but declining to offer any specific details.
Initial reports described vicious combat by the fighters remaining in Mosul, believed to number as many as 5,000 or more, including the extensive use of improvised explosive devices and car bombs.