NEW DELHI: India has stepped up security at the US embassy and other American institutions here, deploying as many as 150 police personnel for round the clock security.Allaying US concerns about security of their institutions after barricades outside the embassy here were removed as a fallout of the arrest of senior Indian diplomat Devyani Khobragade , official sources said on Thursday that at any given time 50 police personnel are deployed."As many 150 police personnel are being deployed during a 24-hour period in shifts at the US embassy, School and American Centre in New Delhi. Also, two police vehicles have been permanently stationed along various roads near the embassy including Nyaya Marg," they added.Earlier, there were about 120 police personnel during a 24-hour period for the security of these institutions."There is 24x7 patrolling to ensure smooth flow of traffic and traffic calming measures including speed breakers are in place," said sources while indicating that this level of security is by far the most that is provided to any embassy in New Delhi.The US government has been voicing concerns over the security of their diplomatic personnel after India enforced strict reciprocity by removing the barricades as the US authorities opened the parking in front of the Indian embassy in Washington DC to general public and refused to reinstate it despite repeated requests."The US action has forced India to review these privileges to bring them strictly in line with reciprocity," the sources had said.The government action came after India's deputy consul general Devyani Khobragade, the 39-year-old 1999 IFS officer, was arrested in New York on December 12 on charges of making false declarations in a visa application for her maid Sangeeta Richard and subjected to strip and cavity search, which had sparked outrage in India.