Afghan attackers have launched a coordinated assault on a guest house used by the Red Cross.
They blasted through the gates with a suicide bomber before storming the building and setting off a gun battle. The attack in the eastern city of Jalalabad is the second major assault against an international organisation in five days.
A spokesman for the governor of Nangarhar province, said the assault began just before dusk with a suicide blast at the entrance to the guest house compound belonging to the RedCross.
"The initial reporting shows that two other people have entered the building. Right now a gun battle is going on between the Afghan security forces and the attackers. We have reports of one guard of the guest house being killed as a result of the attack. From the battle we have no reports of other casualties," he said.
The Red Cross said: "We can confirm that there has been an attack on our offices in Jalalabad. We are working to find out the whereabouts and well-being of our colleagues."
No-one claimed responsibility, and it is unclear why insurgents would want to target the Red Cross, which not only carries out humanitarian work around Afghanistan but also is the conduit for families to communicate with detainees taken off the battlefield, including the Taliban.
The Red Cross warned last month that security was deteriorating across Afghanistan as militants flood the battlefield and conduct attacks in what could be the most important spring fighting season of the nearly 12-year-old war.
The violence comes just five days after Taliban gunmen backed by a suicide car bomber attacked the Kabul offices of the International Organisation for Migration, killing two Afghan civilians and a police officer. The assault sparked an hours-long street battle and left another 17 wounded.
The Taliban and others have unleashed a wave of bombings and assassinations around the country, testing the ability of the Afghan security forces to respond with reduced help from international forces, who have begun a withdrawal that will see most foreign troops gone by the end of 2014.
This year is crucial for Afghanistan as the coalition is expected to hand over the lead for security in Afghanistan to the country's security forces sometime in the late spring. Foreign military forces are then expected to begin a massive withdrawal that will culminate at the end of next year.
Earlier, seven insurgents wearing police uniforms and bomb-laden vests attacked a government compound in Panjshir, a usually secure province in eastern Afghanistan. One police officer was killed and another was wounded.