Lucknow: The toll in the Mathura violence rose to 20 on Friday as Superintendent of Police Mukul Dwivedi and others injured in Thursday's clash between police and encroachers during an anti-encroachment drive, succumbed to their injuries, officials said. While 250 people have been detained for their involvement in the incident, the city continues to be tense even as heavy police reinforcement has been deployed in the violence hit region. Dwivedi, a 1995 batch officer had joined as SP (City) Mathura seven months ago and is being remembered as one of the finest in the district police force. He was leading the operations following the orders of the court to clear the park of encroachment when police team was greeted with unprovoked and indiscriminate firing by the encroachers, believed to be part of sect called 'Satyagrahis'. While Chief Minister Akhilesh Yadav has ordered a probe into the incident, sources say the slain SP many times in the past had shared his frustration about the situation in Jawaharbagh, with friends and family. Close aides said that Dwivedi had spoken to them on how his superiors in the district were dissuading him against acting against the people behind the encroachment, despite a specific court order to do so. He also allegedly told some officials that he was not being provided with adequate police force to clear the encroachment at the sprawling park. The incident has come as a setback to the Samajwadi Party (SP) government in the state which braces for elections early next year and is already faced with charges of lawlessness in the state. Bharatiya Janata Party (BJP) state spokesman Vijay Bahadur Pathak told IANS that while the incident was very unfortunate it did not come as a shock as "in the past too, policemen have been targetted even as chief minister and his government have been in a state of denial". "It is very sad that on one hand the people of the state are victims of lawlessness and even the police in the last four years has been targetted" he said while seeking action against the Mathura DM and SSP for intelligence failure. The Bahujan Samaj Party (BSP) and Congress leaders have also slammed the state government for letting the situation spin out of control to such fatal consequences.