KABUL, Afghanistan (AP) — David Gilkey, a veteran news photographer and video editor for National Public Radio, and an Afghan translator, Zabihullah Tamanna, were killed while on assignment in southern Afghanistan on Sunday, the network says.

Gilkey and Tamanna were traveling with an Afghan army unit near Marjah in Helmand province on Sunday when the convoy came under fire and their vehicle was struck, the network’s spokeswoman, Isabel Lara, said in a statement. Two other NPR journalists, Tom Bowman and producer Monika Evstatieva, were traveling with them and were not hurt.

Secretary of State John Kerry called the attack that killed Gilkey and Tamanna “a grim reminder of the danger that continues to face the Afghan people, the dedication of Afghan national defense and security forces to securing their country, and of the courage of intrepid journalists – and their interpreters – who are trying to convey that important story to the rest of the world.”