DUBAI, Feb 24 (Reuters) - Demonstrators marched in Iran's restive southeast on Friday amid reports on social media that security forces were surrounding a mosque at the centre of weekly anti-government rallies. Anti-government protests have been taking place across Iran since last September's death in custody of 22-year-old Kurdish Iranian woman Mahsa Amini for flouting hijab policy, which requires women to entirely cover their hair and bodies. Commerce Department targeted Belarus, Iran and others in its latest response to Russia's invasion of Ukraine, imposing export control measures and adding more targets to its entity list