UPDATED 3:17 p.m. EDT -- The Pentagon identified the U.S. Marine killed in a rocket attack in northern Iraq as Staff Sgt. Louis F. Cardin, of Temecula, California. Cardin was killed by indirect fire during a rocket attack carried out by the terror organization known as the Islamic State group, near the city of Mosul, Iraq. He is the second U.S. soldier to be killed in Iraq since the start of operations against ISIS.

Original Story:

The U.S. military said a group of marines was on the ground in Iraq Sunday to fight the Islamic State group, or ISIS, Reuters reported. The marines joined a coalition of forces battling the terror group in Iraq and Syria.

The news came one day after indirect fire killed a U.S. soldier near the ISIS stronghold of Mosul in northern Iraq and less than a week after Secretary of State John Kerry declared that ISIS was committing genocide. The fatality was the second U.S. military death in Iraq since operations began against ISIS.

Daesh is genocidal by self-proclamation, by ideology, and by actions — in what it says, what it believes, and what it does,” Kerry said Thursday, using another name for the Islamic terror group and citing atrocities it has committed against Yazidis, Christians and Shiite Muslims. The potential acts of genocide “must be brought to light by an independent investigation and through formal legal determinations made by a competent court or tribunal,” he added.

A fragile ceasefire remained in place in neighboring Syria, where a U.S.-led coalition has been battling ISIS as multiple Syrian opposition groups struggle to overthrow Syrian President Bashar Assad. The U.S. has led airstrikes in coalition with France, Saudi Arabia and several international powers while attempting to limit U.S. boots on the ground by instead arming and training several of the Syrian rebel fighter groups.

The ceasefire, established in February, served as a brief respite in a civil war that began more than five years ago after anti-government protests turned violent in 2011. Reports have surfaced, however, that fighting has continued despite the ceasefire, according to monitoring groups.

The international geopolitical landscape in Syria has grown more complicated over the past several weeks, following a declaration from Russia that it would conduct a partial withdrawal of its troops from Syria. Russia had been conducting airstrikes since September 2015, fighting ISIS particularly in regions where the group threatened Assad’s regime.