Amnesty International has called on the Yemeni authorities to protect a human rights activist and journalist who is alleged to have indirectly received a death threat from a high-ranking official for her role in organizing and taking part in the continuing mass protests in the country. Fears for Tawakkol Karman's safety arose after her brother received a phone call on Wednesday implying that his sister would be killed if he did not ensure she stayed at home. The threat came as tens of thousands of protesters in the capital Sana'a continued to call for economic reforms, an end to corruption and for Yemeni President Ali Abdullah Saleh to stand down. Tawakkol Karman, the president of Yemeni NGO Women Journalists without Chains, was arrested on 23 January for taking part in a student demonstration in Sana'a over the weekend. The demonstration expressed solidarity with ongoing protests in Tunisia and called for an end to the rule of the current president, who has been in power since 1978. She was released a day later and charged with taking part in an unlicensed protest. Dozens of other activists were also arrested and charged with the same offense. “The Yemeni authorities must treat this alleged threat to Tawakkol Karman seriously and take urgent action in accordance with her wishes to ensure she is not subjected to further intimidation or to physical harm,” said Philip Luther, Deputy Director for the Middle East and North Africa at Amnesty International. “They must conduct an immediate, impartial and thorough investigation into the threat and hold anyone responsible to account, no matter how senior their position may be.” Tawakkol Karman's brother is reported to have received the phone call on 26 January telling him that either he should confine his sister to her house or “those who weaken the whip of obedience would be killed”. Tawakkol Karman told Amnesty International that she takes the threat seriously. The Yemeni government has been resorting to repressive and illegal methods to quash dissent, with human rights activists, journalists and students targeted. “Although yesterday's mass protest appeared to be tolerated and passed off without major incident, the authorities what appear to be increasing attacks targeting civil society activists involved in organizing or taking part in peaceful demonstrations,” said Philip Luther. Freedom of expression is guaranteed by Yemen's Constitution. However, this right is undermined by restrictive laws and practices, particularly the 1990 Press and Publications Law, and by the Specialized Press and Publications Court set up in May 2009. The court appears to be aimed at suppressing dissent by fast-tracking cases brought against government critics. Amnesty