BAGHDAD (AP) — Thousands of members of Iraq’s umbrella of mostly Shiite militias known as Popular Mobilization Forces marched in a parade Saturday, the largest show of strength since the founding of the controversial paramilitary group.

Russian-made tanks, boats, rocket launchers and ammunition were on display in the parade in Diyala province, north of Baghdad, held to mark the seventh anniversary of the formation of the PMF, established after a 2014 call to arms by Grand Ayatollah Ali al-Sistani to defeat militants from the Islamic State group.

At the time, IS held a third Iraq's territory and the Iran-backed militias were critical to boosting the Iraqi government forces, which aided by the U.S.-led coalition eventually defeated the Islamic State group.

However, a rift has recently emerged between the paramilitary force and the government, following the arrest of PMF commander Qassim Musleh last month on terrorism charges. Musleh was later released, a move that embarrassed Iraq’s leadership and laid bare the limits of the government’s ability to bring militia leaders to account.

Also on Saturday, a bomb-laden drone struck a building in an empty village just 3 kilometers (2 miles) from the new location of the U.S. Consulate in Irbil, in Kurdish-run northern Iraq. The building was still under construction and there were no casualties, according to a senior Kurdish official who spoke on condition of anonymity because he was not authorized to talk to reporters.

Rockets and drones have continued to target the U.S.-led coalition across Iraq, with Western officials blaming Iran-backed Shiite militias. Iran-backed groups have become the most powerful and influential within the PMF.

The parade, held in Camp Ashraf, saw Russian-made tanks, boats and locally made rocket launchers come down a broad thoroughfare. The event was broadcast on Iraqi state TV.

Also taking part in the parade were PMF units with Yazidi militiamen, who marched wearing their ceremonial white, as well as Christian and Sunni groups.

The marchers also held large posters of Abu Mahdi al-Muhandis, a top militia leader killed in a U.S.-led airstrike last year outside the Baghdad airport. The strike also killed top Iranian commander, Gen. Qassim Soleimani of the Revolutionary Guard's Quds Force, whose slaying came close to pushing Iran and the U.S. into full-blown conflict.

However, though PMF often brandishes Soleimani's image together with that of al-Muhandis at the paramilitary banners that line the streets of Baghdad and elsewhere in Iraq, images of the Iranian general were absent from the parade — likely an attempt to project cross-sectarian unity of the militias.

Iraqi Prime Minister Mustafa al-Kadhimi, officially the country's commander-in-chief, presided over the parade.

“We affirm our work is being done under the flag of Iraq, and the protection of its land and its people is our duty,” he tweeted during the parade.

Also conspicuously absent from the parade were militias affiliated with firebrand cleric Muqtada al-Sadr and al-Sistani, a sign of deepening divisions within the PMF and dissatisfaction with the growing influence of Iran-backed groups.