The soldiers are said to have gone missing from their post close to Iran's border with Pakistan.
On 31 December, a caller speaking on behalf of a group calling itself Jundollah (God's Soldiers) told the Al-Arabiya television station that the group wants Tehran to release 16 jailed members of its group in exchange for the soldiers.
News agencies quote Iranian officials as saying they are investigating the report.
RFE/RL Iran Report
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