Unidentified armed men blew up on Thursday a main oil pipeline in Marib province, Yemen, for the second time within 10 days. Yemeni Ministry of Defense has accused members of the armed tribal which belong to the Islamic opposition party, Islah , of blowing  up the oil pipeline which derives  from Marib refinery, north east of Yemen to the export port in Ras Issa in the western province of Hodeidah Yemen. The ministry said in a statement that "the militia blew up the pipe after less than 24 hours of reconstructing the pipe which had been subjected to a similar explosion in the middle of this week." Yemen has witnessed various operations targeting oil pipelines in Marib province since the start of the political crisis in Yemen, which has resulted in a crisis in Yemen for more than 4 months ago