Police in UP’s Agra district have arrested a man who is alleged to have run over and killed a 24-year-old police constable after he tried to stop his tractor-trolley laden with illegally- mined sand on Sunday near UP-Rajasthan border. Apart from the main accused, Prakash, eight others allegedly involved in illegal sand mining and part of his gang were also arrested from different parts of the district on Wedne-sday. District police are now mulling invoking stringent Gangster Act against them. SP rural (west), Agra, Ravi Kumar said that all the accused are suspected to have criminal records, and they are residents of Rajasthan. Police said that Prakash had also opened fire at them in a bid to flee while he was being arrested.