TEHRAN, Oct. 18 (Xinhua) -- Iran has called for a joint operation with Pakistan to set the Iranian border guards free, who were kidnapped on Tuesday and were transferred to the Pakistani soil, Press TV reported on Thursday.

In a letter to his Pakistani counterpart, Iran's Interior Minister Abdolreza Rahmani Fazli urged Islamabad to fully honor its obligations under bilateral security agreements which require Pakistan to prevent attacks targeting Iranian border posts from the Pakistani side.

In the letter issued on Wednesday, Rahmani Fazli announced Iran's readiness for joint operation with Pakistan to free the Iranian guards.

On Tuesday, 14 Iranian border guards were kidnapped by an armed group in Mirjaveh border point in Iran's southeastern Sistan and Baluchestan Province.

Sistan and Baluchestan Province, bordering Pakistan, is the locus for frequent armed clashes between the Iranian security forces and armed rebels or smugglers.