Several blasts hit a position held by Iran-backed militias in Iraq (IMIS) next to Balad air base north of Baghdad on Tuesday, an Iraqi military official and a source in a paramilitary group said.
It was one of a series of explosions in recent weeks at weapons depots, bases or positions belonging to factions within the IMIS, Iraq's umbrella of mostly Shiite paramilitary groups.
Balad base hosts US forces and contractors and is located about 80 kilometers (50 miles) north of Baghdad. The IMIS group backed by Iran is stationed nearby.
The military official said the intended target of the blasts was the group's position near the base. The paramilitary source said his group's weapons depot was specifically targeted by an aerial bombardment.
Iraq's Defense Minister Najah al-Shammari visited the site shortly after the incident, and told Iraqi state television that fires resulting from the blast had been put out and that some military personnel had suffered minor injuries.
The US-led coalition could not immediately be reached for comment.
Witnesses said the explosions caused stored rockets to fly into nearby farmland and into Balad base itself, and residents in the area fled their homes fearing rockets might land on them.
A blast last week at a weapons depot run by an IMIS group sent rockets careening across southern Baghdad, killing one person and wounding 29 others. Police at the time attributed the explosion to poor storage and high temperatures, but a government investigation is underway.
In July explosions at a base belonging to Iran-linked groups wounded two people. A security source said one blast had hit an ammunition depot.
Prime Minister Adil Abd al-Mahdi last week ordered all ammunition dumps belonging to the armed forces or paramilitary groups to be moved outside of cities.
He also cancelled all special flight permissions for Iraqi and foreign aircraft, meaning sorties including by the US-led coalition operating against ISIS militants must be cleared in advance by the prime minister.
Some analysts have suggested the strikes might have been carried out by Israel, which last year signaled that it could attack suspected Iranian military assets in Iraq, as it has done with scores of air strikes in Syria.
"Iraq's air defenses have very high capability, but one thing they couldn't detect is an advanced Israeli air attack," said Baghdad-based security analyst Hisham al-Hashimi, who advises the government.
Israeli officials have suggested recently they view Iraq, whose main ally is Israel's regional foe Iran, as more of a threat than in recent years, but have not directly commented on the recent blasts at IMIS sites in Iraq.
The US coalition has denied any involvement in the recent explosions.