The U.S. military has confiscated Bibles that Christian U.S. Soldiers in Afghanistan had apparently intended to give to local Muslims, a military spokesman has said.
Al Jazeera broadcast footage on Monday that showed troops apparently preparing to convert Afghans to their faith.
Some of the Soldiers who appeared in the video have also been reprimanded, U.S. government and military officials told Al Jazeera's James Bays.
The video, shot about a year ago, appeared to show military chaplains stationed in the U.S. air base at Bagram discussing how to distribute copies of the Bible printed in the country's main Pashto and Dari languages.
Adm. Mike Mullen, the chairman of the Joint Chiefs of Staff, told Al Jazeera he was not aware of the details of the footage but that the U.S. Army was not involved in promoting religion.
"From the United States' military's perspective, it is not our position to push any specific kind of religion," he said at a Pentagon briefing in Washington on Monday.
In one recorded sermon, Lt. Col. Gary Hensley, the chief of the U.S. military chaplains in Afghanistan, tells Soldiers that, as followers of Jesus Christ, they all have a responsibility "to be witnesses for him".
"The special forces guys -- they hunt men basically. We do the same things as Christians, we hunt people for Jesus. We do, we hunt them down," he says.
"Get the hound of heaven after them, so we get them into the kingdom. That's what we do, that's our business."
Questioned about the footage, Greg Julian, a U.S. colonel in Afghanistan, told Al Jazeera: "Most of this is taken out of context ... this is irresponsible and inappropriate journalism.
"This footage was taken a year ago ... the Bibles were taken into custody and not distributed.
"There is no effort to go out and proselytise to Afghans."
'Very damaging'
Under the U.S. military code of conduct, armed forces on active duty are prohibited from trying to convert a person's faith.
Ahmed Shah Ahmedzai, a former Afghan prime minister, told Al Jazeera from Kabul on Monday: "This is a complete deviation from what they [the U.S. military] are supposed to be doing.
"I don't think even the U.S. constitution would allow what they are doing ... it is completely against all regulations.
"This is very damaging for diplomatic relations between the two counties ... everyone knows people are very conservative here, very faithful to Islam. They will never accept any other religion.
"Someone who leaves Islam is sentenced very severely -- the death penalty [is imposed].
"There must be a serious investigation now that it has come out into the public and [into the] press," he said.
Sayed Aalam Uddin Asser of the Islamic Front for Peace and Understanding in Kabul told Al Jazeera: "It's a national security issue ... our constitution says nothing can take place in Afghanistan against Islam.
"If people come and propagate other religions which have no followers in Afghanistan [then] it creates problems for the people, for peace, for stability.
The footage shot by Brian Hughes, a documentary maker and former member of the U.S. military who spent several days in Bagram near Kabul, was obtained by Al Jazeera's Bays, who has covered Afghanistan extensively.
In other footage captured at Bagram, Sergeant Jon Watt, a Soldier set to become a military chaplain, said during a Bible study class: "I also want to praise God because my church collected some money to get bibles for Afghanistan. They came and sent the money out."
U.S. military regulations expressly forbid "proselytising of any religion, faith or practice".
The footage also suggests U.S. Soldiers gave out Bibles in Iraq.