KHARTOUM, Aug 20 (Reuters) - Sudan released six people, including one journalist, jailed for almost two months without charge after riots in the northern town of Kajbar where police killed four people, the journalist said on Monday. Police fired live rounds and tear gas on Sudanese protesting in June against plans to build a new dam in Kajbar in northern Sudan, killing four people and injuring others. The police said they acted in self-defence. Video footage recorded of the event and posted on the Internet showed police on a hill above protestors opening fire. "They kept asking me about my relation to the people of Kajbar and I kept saying I have no relation to them - I am not from the area ... and am just doing my journalistic duty," Mujaheed Abdullah from the opposition al-Rai al-Shaab daily told Reuters after his release. He and five others detained after the protests were released on Sunday evening after almost two months detention without charge and without any visits by lawyers or family. "They told me not to write anything about this -- if I do I will be arrested again for inciting chaos," he said. He added he was not questioned by anyone from the Justice Ministry, only national security forces. Abdullah said he was not tortured but conditions were difficult personally. "I did not see the sun except to pray for five minutes at a time and was only near the end allowed to do any kind of exercise," he said. He added one person was still under arrest, Mohamed Jalal.