KABUL, Afghanistan — Two U.S. servicemembers were killed Wednesday when an explosive-laden vehicle blew up near a NATO convoy outside a base in the southern city of Kandahar, the U.S. military said.

Navy Capt. Jeff Davis, a Pentagon spokesman, announced the two deaths but withheld names of the victims. Their deaths bring to 9 the number of U.S. combat fatalities in Afghanistan this year.

Kandahar police spokesman Zia Durrani said a vehicle parked alongside the road was detonated as the convoy drove by. Earlier reports indicated the attacker had sped toward the NATO convoy. Local media, quoting the Kandahar governor’s office, said one military vehicle was damaged in the blast.

The Taliban claimed responsibility for the attack. They said in a statement that a suicide bomber detonated a pickup truck, destroying two armored vehicles and killing 15 foreign troops, including two generals. The Taliban routinely embellishes their claims.

Ghulam Ali, who runs a mechanics shop near the attack site on the outskirts of the city of Kandahar, told The Associated Press the blast was so intense that it knocked him out.

When he came to, he saw a military vehicle on fire on the road. He stepped out of his shop but a sudden burst of gunfire drove him back inside, he said. Then, helicopters arrived and he saw soldiers being taken away from the scene but could not determine the extent of their injuries, the AP reported.

The Taliban claimed responsibility for the attack.

The Taliban, which originated in Kandahar in the 1990s, said the convoy was targeted as it returned to Kandahar Air Field after a meeting at the provincial governor’s residence. U.S. and NATO troops are based at the airfield, the country’s second largest military base, about 14 miles south of the city center.

Afghanistan’s TOLO News also reported that the insurgents this week have been battling Afghan forces north of Kandahar along the highway linking the city to the country’s capital of Kabul about 300 miles away.

NATO’s 39-nation Resolute Support mission in Afghanistan consists of 13,500 troops — about 7,000 of them Americans. The Trump administration is deciding whether to send about 4,000 or more U.S. troops to stem Taliban gains in the nearly 16-year war.

NATO and Afghan government forces are also battling an Islamic State affiliate that has gained a foothold in the country and has carried out a number of high-profile attacks.

Wednesday’s blast in Kandahar occurred a day after a suicide bomber stormed into the largest Shiite Muslim mosque in western Herat province, opening fire on worshippers before blowing himself up. That attack killed at least 29 and wounded 64 others.

No group claimed responsibility for the mosque attack, but ISIS has warned Shiites that they would be targets. The Sunni militant group views the Shiites as apostates.

Herat is located about 500 miles west of Kabul, far from areas of eastern Afghanistan where ISIS normally operates.

Stars and Stripes reporter Corey Dickstein contributed to this report.

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