Two U.S. service members were killed Wednesday when their convoy came under attack in Afghanistan's Kandahar Province.

An Afghan police official in Kandahar said a suicide bomber hit the convoy of international troops on the edge of the southern city of Kandahar. NATO officials also confirmed the attack.

“Resolute Support can confirm that a NATO convoy was attacked this afternoon in Kandahar,” a NATO statement read. “The attack did cause casualties.”

The two deaths brings the total number of U.S. service members killed in Afghanistan this year to nine.

The American forces in southern Afghanistan are part of the more than 8,400 troops currently deployed in the country.

The combined U.S. and NATO troop contingent currently in Afghanistan is about 13,500. The Trump administration is deciding whether to send about 4,000 or more U.S. soldiers to Afghanistan in an attempt to stem Taliban gains.

U.S. and international forces operate primarily out of Kandahar Airfield in southern Afghanistan. There are also more than 300 Marines and Army soldiers in neighboring Helmand Province.

Kandahar is considered to be the spiritual home of the Taliban.

News of the bombing comes just a day after two U.S. soldiers were injured when their Black Hawk helicopter made a hard landing in the Achin District.

The Taliban in a statement claimed it opened fire on the helicopter, killing everyone on board. The insurgents routinely exaggerate their gains and casualties they inflict in battle.

On Monday, two attackers stormed the Iraqi Embassy in central Kabul, killing numerous guards before using stick bombs to break through the embassy gates. Police officials told the Associated Press that a car bomb exploded outside the embassy, followed by an attempt by gunmen to enter the building, which is located in the center of the Afghan capital.

In April, two U.S. Army Rangers were killed by ISIS fighters in Achin, just weeks after the U.S. military dropped the “Mother of all Bombs’, or MOAB, on an ISIS cave complex.

The Associated Press contributed to this story.