Updated at 9:35 a.m. ET: Reuters reports that two British soldiers have been arrested for "inappropriate behavior" in Afghanistan, according to the British Ministry of Defence.
Afghan President Hamid Karzai said in a statement that the government in Kabul was "deeply disturbed" by reports of abuse, and said their alleged behavior was "immoral."
The alleged incident comes just a week after a video emerged showing U.S. Marines urinating on corpses, believed to be dead Taliban fighters, that caused outrage across Afghanistan.
"The government of Afghanistan is immensely disgusted by the rise in recent incidents of immoral nature among foreign soldiers that clearly undermine public confidence and the Afghan people's cooperation with foreign troops," Karzai's office said.
The Royal Military Police have launched an investigation into allegations against the two soldiers, a ministry spokesman said, but declined comment on the nature of the allegations.
"Two service personnel have been arrested, interviewed under caution and released," the spokesman said, adding that the ministry took any such allegations extremely seriously.
Published at 7 a.m. ET: The Sun reported that Prime Minister David Cameron was "deeply shocked" in the wake of claims that the pair, a sergeant and a private, filmed the separate incidents involving a boy and girl aged around 10. The two then reportedly showed the footage to other servicemen, the newspaper reported.
Defense officials who informed Cameron of the allegations told him that the pair had been arrested, The Sun reported.
The U.K.'s Ministry of Defense said it was taking the allegations "extremely seriously."
"We are aware that an allegation has been made concerning alleged inappropriate behaviour by two servicemen in Afghanistan. The Royal Military Police (Special Investigations Branch) has launched an investigation into this," it said in a statement to msnbc.com. "It would be inappropriate to comment further while an investigation is ongoing."
The allegations come just days after the American military was hit by video showing Marines urinating on Taliban corpses.
Two UK soldiers serving in Afghanistan have been arrested after they allegedly encouraged two children to touch them inappropriately through their clothes, a British newspaper reported on Wednesday.
Reuters and msnbc.com staff contributed to this report.