The U.S.-led military coalition against the Islamic State in Iraq and Syria has killed about 45,000 ISIS fighters in the last two years, its commander said Wednesday.
Army Lt. Gen. Sean MacFarland, commander of the task force overseeing the war, said since he took over last September, about 25,000 ISIS fighters have been killed.
"When you add that to the 20,000 estimated killed prior to our arrival, that's 45,000 enemies taken off the battlefield," he said during a Pentagon briefing.
The U.S. military has typically declined to give the number of enemy dead, to avoid the Vietnam War practice of using "body counts" as misleading measures of success.
However, MacFarland, who is wrapping up his 11-month tour in Baghdad, added, "I only tell you this number to provide a sense to the scale of our support and perhaps explain why enemy resistance is beginning to crumble."
The three-star general said ISIS's frontline fighters are diminishing in quantity as well as quality, and are easier to kill.
"We don't see them operating nearly as effectively as they have in the past, which makes them even easier targets for us so as a result they're attrition has accelerated here of late," he said.
ISIS has taken a lot of their "administrative folks" and pushed them out to the front lines, he added.
"So there is a cumulative effect, I think, that is really accelerating in our favor and against the enemy," he said.
MacFarland said he's seen estimates of between 15,000 to 30,000 ISIS fighters remaining, but declined to give a more specific number.
He also said the coalition has helped Iraqi forces gain back 25,000 square kilometers from ISIS in Iraq and Syria -- nearly half of what ISIS controlled in Iraq and 20 percent of what they controlled in Syria.
The coalition has also conducted about 50,000 sorties against ISIS in the past year, which include 200 against oil and natural gas activities, more than 640 oil tankers, and other critical gas and oil facilities, he said.
The strikes have reduced ISIS's oil revenue stream by 50 percent, he said. The coalition has also hit more than 25 bulk cash sites, destroying at least a half billion dollars, he added. The coalition has also taken out leadership, command and control and weapons manufacturing capability, he said.
He also noted the deaths of three U.S. service members.
"Sadly, success has not come without cost. We lost three great Americans during our time here; Army Master Sergeant Josh Wheeler, Marine Corps Staff Sergeant Louis Cardin, and a Navy Petty Officer First Class Charles Keating," he said.
Iraqi and Kurdish forces have suffered from hundreds of casualties, too, he said.
MacFarland said ISIS "is in retreat on all fronts," with the turning point being the recapture of Ramadi from the group in December.
The coalition is now training Iraqi military and police forces to retake Mosul, and hold it afterwards. The city is Iraq's second largest, with about a million residents, and has been an ISIS stronghold since June 2014.
MacFarland said the coalition has trained more than 13,500 Iraqi forces, including more than 4,000 army soldiers, 1,500 elite forces, 6,000 Kurdish peshmerga and almost 1,000 federal police and 300 border guards.
It has also trained about 5,000 local police and enrolled over 20,000 tribal fighters, he added.
MacFarland said he is "100 percent certain" that ISIS will be "eliminated as a governing entity in Iraq and Syria."
After retaking Mosul, there would be only "scattered pockets" of resistance in Iraq. In Syria, the fight is focused on retaking ISIS's stronghold of Raqqa, he said.
Coalition-backed Syrian Democratic Forces are close to retaking Manbij, a strategic node where ISIS takes in foreign fighters and facilitates attacks outside of Iraq and Syria, he said.
However, he noted, "Military success in Iraq and Syria will not necessarily mean the end of Daesh," he said, using the Arabic acronym for ISIS.
"We can expect the enemy to adapt, to morph into a true insurgent force and terrorist organization capable of horrific attacks like the one here on July 3rd in Baghdad and those others we've seen around the world," he said.