Authorities in Afghanistan have identified up to six people they want to question about the killing of two German journalists shot dead while camping, a senior official said on Sunday.
The Germans, a woman and a man who had worked for Deutsche Welle radio, were killed in the early hours of Saturday when gunmen attacked them in their tent in Baghlan province, about 120 km (80 miles) north of Kabul.
"We have identified from four to six people in the area where the attack took place," said the governor of Baghlan, Sayed Ikram Mahsomi. "We are going to make arrests as soon as we get more information."
The German radio station identified the victims as freelance journalists Christian Struwe, 38, and Karen Fischer, 30, and said they had been on a private trip when the attack occurred.
"We are deeply moved by the death of our colleagues," Deutsche Welle manager Erik Bettermann said in a statement. "Our sympathy goes out to their relatives and we wish them strength at this difficult time."
German Foreign Minister Frank-Walter Steinmeier condemned the killing and urged quick action to bring the perpetrators to justice.
"The gruesome, mindless killing of our citizens only strengthens our resolve to support the Afghan government as it strives for security and the rule of law," he said.
Mahsomi said on Sunday the Germans had not been robbed and called the attackers "government opponents". "They just wanted to kill them to disrupt security," he said.
Violence has surged across Afghanistan this year, mostly in the south and east where Taliban militants have been battling foreign and government troops. Attacks have also taken place in Kabul, the west and the north, but Baghlan had been quiet recently.
A Taliban spokesman, Qari Mohammad Yousuf, said the Taliban were not responsible.
The two journalists were travelling from Baghlan to the central province of Bamiyan when they stopped to camp for the night on Friday evening.
They had just spent time with German NATO troops in the north of the country. Germany has a contingent of about 2,750 troops with NATO's Afghan mission.
Deutsche Welle said Struwe had helped with the creation of an international editorial department at Radio Television Afghanistan. It said Fischer had helped report on the Afghan elections last year.
"It is tragic that Karen Fischer and Christian Struwe had to die in the country they had dedicated so much of their personal efforts to supporting," Bettermann said.