Prime Minister Mustafa al-Kadhimi announced on Monday that “a group of suspects” have been arrested for their role in the Sunday attack, but did not specify the exact number of suspects.
He said the Iraqi military has also arrested the officials responsible for ensuring the security of the area from which the rockets were launched.
"The attack on the Green Zone was a cowardly terrorist act," he said, adding that attacks on diplomatic sites are not acceptable at all.
At least eight rockets landed close to the US diplomatic mission on Sunday night, causing sirens blaring within the compound without any casualties apart from some material damage.
Following the attack, the Iraqi military said in a statement that an "outlaw group" had fired rockets at Baghdad's Green Zone.
The rockets hit a residential complex inside the Green Zone, damaging buildings and cars, but causing no casualties, the statement added.