Senior IPS officer Sulkhan Singh took charge as the 66th Director General of Police (DGP) of Uttar Pradesh on Saturday.The 1980-batch officer, soon after taking over the reins of one of the biggest police forces, warned criminals to mend their ways and asked officials to ensure that rule of law prevailed in the state."Nobody will be allowed to take law in their hands," he declared, asking officials to crack down on criminals and ensure that the people lead a safe and secure life.The police will work in a fair and unbiased manner, he said.According to him, all efforts will be rolled out to win the confidence and trust of the people.Known for his upright nature and professional acumen, Singh was picked up by the new Bharatiya Janata Party government on Friday to replace Javeed Ahmad as the top police official.Singh in his first briefing told the reporters that the force's strength would be increased with fresh recruitment.He said serious and sustained efforts would be made to ensure that the image of police gets a pro-people makeover.He also exhorted the police personnel to put in their best to serve the people and ensure that the rule of law prevails in Uttar Pradesh.