Tens of thousands of Yemenis demanded President Ali Abdullah Saleh’s execution in protests Sunday against his immunity from prosecution over a deadly crackdown on dissent. “It is our duty... to execute the butcher,” chanted angry protesters gathered in the Yemeni capital’s Change Square, the epicenter of the democracy movement that has been calling for Saleh’s ouster since January last year. Yemen’s parliament on Saturday adopted a law giving Saleh “complete” immunity from prosecution in return for stepping down under a Gulf-brokered transition deal. The law also offers partial protection from legal action for Saleh’s aides, saying the president’s lieutenants cannot face prosecution for “actions that were politically motivated and carried out in the exercise of their duties.” The protesters carried banners calling on lawmakers to reverse their decision. “To the lawmakers, we say there will be no immunity at the expense of the blood of our martyrs,” referring to the hundreds killed in the government crackdown. The demonstrators tried to march to the U.S. embassy in Sana’a but were stopped by Yemeni security forces. The final text of the immunity law specified the amnesty “does not apply to acts of terrorism,” though no further details were revealed as to what actions may fall within that category. The transitional government of national unity, which is led by the parliamentary opposition, had submitted 11th-hour amendments on Friday reducing the scope of the amnesty offered to the president\'s aides following a public outcry. U.N. envoy to Yemen, Jamal Benomar, has criticized the immunity law arguing it neglects the rights of “victims.” Speaking to reporters before departing Yemen late Saturday, Benomar said that though “the law was amended... it does not live up to our expectations. The U.N. in principle stands against this type of blanket immunity.” He further called on parliament to enact a “transitional justice and reconciliation” law that would allow victims to be heard and make claims for compensation. Parliament also adopted a law approving Saleh’s longtime deputy, Vice President Abdrabuh Mansur Hadi, as the consensus candidate in the election for Saleh’s successor, which is due to be held on February 21.