Ottawa (AFP) - Canada's first airstrikes against Islamic State jihadists in Iraq destroyed heavy engineering equipment used to build up group's defenses and divert water from the Euphrates River, an official said Tuesday.

Lieutenant-General Jonathan Vance told a press conference two CF-18 Hornet fighter jets dropped several 500-pound laser-guided bombs on four targets near a dam near Fallujah.

IS, he said, had been using the equipment to "divert water from the Euphrates river to create flooding and displace the population in Anbar province, and denying water to other populations downstream."

By flooding specific areas, IS forced civilians and Iraqi troops to use "specific roads where they had placed improvised explosive devices or IEDs," he explained.

Furthermore, the militants used the vehicles to "develop and enhance their defensive positions, which would have made future clearing operations for the Iraqi security forces more difficult."

Canada conducted its first airstrikes in the anti-IS fight following two days of reconnaissance after joining the coalition last Thursday.

Vance said Canadian aircraft have flown a total of 27 sorties in Iraq so far.