CANBERRA, Australia — Islamic State fighters were increasingly using Mad Max-style suicide vehicles and commercial drones armed with grenades in their defense of the Iraqi town of Mosul, Australia's defense chief said Wednesday.

Air Chief Marshal Mark Binskin likened the vehicles used by the Islamic State group against Iraqi government troops to those featured in the George Miller-directed post-apocalyptic movie franchise.

Multiple attacks by explosive vehicles were the group's first line of defense, Binskin told a Senate committee.

"These could come as just vehicles that are loaded (with explosives), but more likely now in what you would hear termed 'Mad Max vehicles' — lots of steel around them, small slits for the drivers to see, and they're predominantly suicide attacks," Binskin said.

An Iraqi officer holds a drone belonging to Islamic State militants in Mosul, Iraq, on Jan. 27, 2017.

Photo Credit: Khalid Mohammed/AP

The militants were also increasingly using publicly available drones armed with grenades and other small weapons over the urban environment of west Mosul.

The threat was "enough to create havoc and, if you're in the wrong spot, kill you," Binskin said.

Binskin said Iraqi troops use a range of tactics against such attacks, but he declined to detail them.

"They are limited in what they can do, but in close-in, urban fighting, they have the range to create problems for the assaulting force," Binskin said.

Iraqi forces launched a push to take the western half of Mosul from ISIS last week and have so far captured the city's international airport and a sprawling military base next to it as well some neighborhoods from the southern edge. Iraq declared eastern Mosul "fully liberated" in January, after three months of fierce fighting.

Australia provides fighter jets to the U.S.-led coalition that supports Iraqi troops.

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