Robert Coalson contributed to this story from Prague

VRADIYIVKA, Ukraine -- Locals in the south-central Ukrainian town of Vradiyivka have suspected something was very wrong in their police department for many years.Their anger exploded into outraged protest last week when hundreds of townspeople stormed the police station after 29-year-old Iryna Krashkova accused two police officers and a local townsman of beating and raping her on June 29.The government has promised a thorough investigation of Krashkova’s allegations. The three accused are currently in custody.What’s more, prosecutors have begun reexamining old cases that Vradiyivka residents say were covered up in the past.In January 2011, 15-year-old Alina Porkul was raped and murdered. Alina’s father, Igor Porkul, tells RFE/RL's Ukrainian Service that the two cases are similar, at least on the surface."Judging by the photographs of our daughter and Iryna, the attacks were identical, similar," Porkul says. "Their heads were beaten. Their eyes were also beaten -- their left eyes and right cheeks. [Iryna] was able to survive her attack, but our daughter was thrown into some water, into a pond."Porkul adds that no fingerprints were found on his daughter’s possessions -- not even hers -- indicating to him that "the perpetrator knew what he was doing."Regional prosecutor Andriy Kurys has confirmed that his office has reopened the investigation into Alina Porkul's murder.Locals in Vradiyivka say that one of the police officers named by Krashkova has long had a reputation as a drunkard and a "sadist," and they believe he has been protected for some time because of family political connections.Although the Porkul case is officially unsolved, 11 men have reportedly confessed to involvement in the crime. Two of them committed suicide after confessing, one while in police custody; activists believe the confessions were extracted under torture.Prosecutor Kurys has also confirmed that his office is reinvestigating the two alleged suicides.While the Porkul case was being investigated in 2011, Oleksandr Pidhurskyy allegedly hanged himself in a jail cell after being held by police without outside contact for seven days.Pidhurskyy’s mother, Vera, says she does not know to this day why her son was detained."I didn't know why they took him away. Maybe they wanted him to sign something. We’ll have to find out," Pidhurska says. "He managed to tell me they hadn't given him any food or even water for three days. I took him some food on the fifth day and they tore the bag out of his hands and told him: 'You’ll do what you have to do and then you will eat.'"Pidhurska joined the protest at the Vradiyivka police station. She says she was shocked to see the police officer who arrested her son standing near Deputy Interior Minister Viktor Dubovik as he tried to mollify the angry crowd.She has applied to the Interior Ministry to investigate her son’s death but has not received any reply.Ihor Slobodyanyuk, a member of the Ukrainian Union of Psychotherapists, tells RFE/RL's Ukrainian Service that the unexpected explosion of violence and anger at the Vradiyivka police station indicates there may be much to investigate there."This isn't an isolated case. A lot has happened there," Slobodyanyuk says. "Local residents -- if they speak about how it is hard for them to look police officers in the face, about how they look down [in such encounters] -- this means they lived practically under a reign of terror. And it was this contained tension that, naturally, produced such violent consequences."Activists in Ukraine say the situation in Vradiyivka is far from unique and that frustrations with the alleged impunity of law enforcement officials and politicians are widespread.Volodymyr Chemerys is a rights activist with the For Peaceful Protest nongovernmental organization in Kyiv."Social tensions in Ukraine are accumulating and becoming more and more acute," Chemerys says. "Ukraine has long been pregnant with revolution. And we can see this because there are more and more protests, and more and more they are focused on social issues."He points to recent demonstrations by victims of the 1986 Chornobyl nuclear power plant disaster and a protest in which coal miners in Luhansk Oblast occupied the mine’s offices.