An unnamed US official claimed that Iranian missile forces across the country were at a “heightened state of alert”, noting that the US military have been closely watching for any further moves by Tehran, Reuters reported.

According to the report, the official said that “it was unclear whether the higher readiness level was defensive in nature or not”.

“They’re clearly at a heightened state of alert. Is that heightened state of alert to be better prepared defensively or to be better prepared offensively? That can’t be determined at this point,” the official was cited by Reuters as saying.

The report comes on the heels of a rocket attack that targeted the so-called Green Zone in central Baghdad. According to Iraqi military statement, six katyusha-type projectiles hit late on Sunday the area with three shells hitting the heavily fortified Green Zone and three others in the nearby Jadriya area.

Tensions escalated following the killing of Qasem Suleimani, the commander of the Iranian Islamic Revolutionary Guard Corps’ elite Quds Force, and Abu Mahdi al-Muhandis, the deputy commander of Iraq’s Popular Mobilization Forces, in a US attack on Friday.