Two British soldiers have been arrested for inappropriate behaviour in Afghanistan, the Ministry of Defence said on Wednesday after a newspaper report of child abuse.

Quoting defence sources, the Sun newspaper reported that the pair had abused two Afghan children aged about ten, and made recordings of their behaviour.

Afghan President Hamid Karzai said in a statement that the government in Kabul was deeply disturbed by reports of abuse, and said their alleged behaviour 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.

A spokesman for the NATO-led coalition in Afghanistan said they were aware of the allegations.

Anti-American feeling has boiled over, or been whipped up, into violence several times in Afghanistan in recent years, including protests over reports of the desecration of the Muslim holy book that twice sparked deadly riots.

The tape of the Marines also prompted reference to earlier scandals involving U.S. soldiers' treatment of prisoners in Iraq and the killing of unarmed civilians in Afghanistan.

The U.S. military has been prosecuting soldiers from the Army's 5th Stryker Brigade on charges of murdering unarmed Afghan civilians while deployed in Kandahar province in 2010.

(Reporting by Emma Graham-Harrison in Kabul, Additional reporting by Estelle Shirbon in LONDON; Editing by Ed Lane)