A doctor and a 16-year-old have been killed in Sudan amid demonstrations against President Omar al-Bashir.

Both were shot in the head by state forces who were firing directly on demonstrators, a member of the Sudan Doctors Syndicate told the BBC. Nine other demonstrators were reportedly wounded in the clashes as protesters staged a sit-in at a hospital in the capital Khartoum. It marks the fifth week of anti-government protests. "Since the beginning, the security forces have responded with excessive use of power and with live ammunition," Dr Amjed Farid said. The doctor who died had "over fourteen live bullets in his body", he added. Protesters had gathered outside the Royal Care International Hospital in the Burri district of the capital for a sit-in. Activists online said security forces used tear gas to disperse the crowds and carried out mass arrests. Protest have also spread to six other cities nationwide, and activists have announced fresh demonstrations beginning on Sunday 20 January. The government has confirmed 24 people have died, but human rights groups say the number could be far higher. First sparked in December by complaints about rising prices, the demonstrations soon morphed into widespread anger against the president's 30-year rule. One Khartoum resident told the BBC there had been economic protests in previous years, "but this time is totally different". "I think people have really had enough. The momentum has been building up," they said. "The number of people demonstrating is rising because of the government violence." UN human rigths commissioner Michelle Bachelet said she was "very concerned" about the situation and called on Sudan's government to respect the people's right to "peaceful assembly". At least 816 people have been arrested so far in the unrest, the UN said. (BBC)