Hundreds of Sudanese protesters rallied on Thursday in Khartoum in support of fellow demonstrators detained in weeks of protests against President Omar al-Bashir's iron-fisted rule, witnesses said.The latest protest came after Bashir acknowledged that Sudan's controversial public order law and growing economic hardships had angered youths and sent them out into the streets.But the veteran leader said on Thursday that "enemies of Sudan" were funding a media campaign backing the demonstrators.The rally was called to express solidarity with the hundreds of demonstrators who have been arrested since anti-government unrest erupted in December.The protesters gathered in the downtown area of the capital, chanting their campaign's rallying cry of "freedom, peace, justice", witnesses said.For almost two weeks a security clampdown had prevented them from converging in the central district."Bring all your soldiers but today you will fall," chanted the protesters, witnesses said, adding that riot police swiftly confronted them with tear gas."The authorities thought we won't be able to reach downtown," a demonstrator told AFP without giving his name for security reasons."It has been difficult, but today we have managed to do it."Protesters also staged rallies in the capital's eastern neighbourhood of Burri and some other areas in Khartoum, witnesses said.Video footage and photographs were swiftly uploaded on social media networks, some showing demonstrators being taken away by security agents. Death in detention Protests first broke out in Sudan on December 19 after a government decision to raise the price of bread.They quickly turned into nationwide rallies against Bashir's three-decade-old rule, with crowds calling for his resignation.Officials say 30 people have died in protest-related violence, while Human Rights Watch says at least 51 people have been killed in clashes with security forces.The Sudanese Professionals Association (SPA) which has led the protest movement called Thursday's demonstrations specifically in support of detainees who it says are being "tortured".Last week, a teacher from the eastern city of Khashm El-Girba in the state of Kassala, Ahmed al-Kheir, died behind bars after he was arrested in connection with the protests, a relative told AFP.His death in custody was confirmed by a top official on Thursday.Amer Ibrahim, the head of a committee at the prosecutor's office investigating protest-related violence, told reporters that Kheir had "died of wounds suffered on his body"."The man had wounds on the back, legs and other parts of his body that led to his death," Ibrahim said."We have asked the chief of NISS in Kassala to bring the security agents who interrogated Kheir in Khashm el-Girba," he said.The chief of the National Intelligence and Security Service (NISS), Salah Ghosh, on January 29 ordered the release of all detainees, but it is unclear how many have been actually freed.Bashir on Wednesday also ordered all detained journalists to be let go. The president, 75, acknowledged that youths, mainly women, were leading the rallies and said the public order law was "one of the reasons" for their anger.Activists say the decades-old law targets mainly women, often accusing them of "indecent dressing and immoral behaviour".Hefty punishments including fines and jail terms are imposed on women found guilty under the legislation.According to some Sudanese women's rights groups, more than 15 000 women were sentenced to flogging in 2016.Bashir, who swept to power in a 1989 Islamist-backed coup, conceded as well that harsh economic conditions, such as high inflation, were also driving the public ire.Protesters out on the streets insist they are seeking a complete change in the country."It's not only the public order law that we are against," said Tahani, a female demonstrator who asked not to be fully named."Once we overthrow the regime, we will change the old laws completely with new laws that respect the dignity and diversity of the Sudanese people."Sign up to News24's top Africa news in your inbox: SUBSCRIBE TO THE HELLO AFRICA NEWSLETTERFOLLOW News24 Africa on Twitter and Facebook.