(CNN) -- Iran's interior minister accused the United States on Saturday of orchestrating the kidnapping of nine Iranian border guards with the help of Sunni militant groups linked to the Taliban and al Qaeda, according to a report.
"The United States, which cannot directly encounter Iran, uses such groups to carry out such acts against the country," Mostafa Pour-Mohammadi told reporters, according to state-run Islamic Republic News Agency (IRNA).
"Iran has launched a serious investigation into the kidnapping. The kidnappers are quite known. They have asked for ransom and release of jailed members of their group in exchange for the release of the border guards," the interior minister said. "We hope our sons can soon return to the country with the least harm."
On Wednesday the Arabic-language network Al Arabiya aired video of what it said were soldiers who were kidnapped near Iran's border with Pakistan.
The network read a statement reportedly made by a Sunni militant group, the Organization of God's Soldiers for Sunni Mujahedeen, threatening to kill the soldiers unless 16 imprisoned fellow militants are released.
The authenticity of the video and the statement cannot be independently verified by CNN.
Iran's government confirmed the soldiers were kidnapped and taken across the border into Pakistan.