Dozens of detainees caught up in a search for militants have gone on hunger strike to protest their imprisonment for more than a year despite having release orders from courts, an Egyptian rights group said Thursday. The 70 detainees have been held since 2004 following an explosion in a packed Cairo market that killed three people including a US and a French citizen. "None of the detainees were put on trial because they did not commit any crime. The reason they were detained is because they were the neighbors of the suspects of the attack," said the Egyptian Organization for Human Rights, the country's oldest human rights organization. The group said the strike was taking place in a prison in the city of Damanhour, 130 kilometers northeast of Cairo. Prosecutors denied the detainees were on hunger strike saying that they have threatened to go on the strike if they are not released soon.