The New York Police Department is providing officers with specialized training to stop any suicide bombers at Sunday’s New Year’s Eve celebration when up to 2 million people will flood the streets of Times Square, officials said on Thursday. The stepped-up training is in response to an attempted bombing in a Times Square subway station walkway on Dec. 11. It comes on top of increasingly stringent security for the city’s New Year’s Eve celebration in the years since the attacks of Sept. 11, 2001. The New York Police Department will also deploy observation teams trained to spot snipers, increase the number of explosive-detecting dogs and position more officers throughout the area this year. Police have said they will incorporate lessons learned from what they have labeled as three terrorist attacks in the city in the past 15 months, in addition to their ongoing analysis of all attacks worldwide. That intelligence will form part of the massive security operation for the “ball drop” celebration, a tradition that dates to 1907 and is now televised around the world. “You will see an increase in heavy weapons, bomb squad personnel, radiological detection teams, and our technology to include over 1,000 cameras in and around the area of Times Square for the event,” the NYPD’s chief of counterterrorism, James Waters, told a news conference, two days before the event. Officers involved in the New Year’s Eve security operation will receive a tactical bulletin and a training video on suicide bombers that they will be able to review on their department-issued phones starting Friday. Sunday is expected to be the coldest New Year’s Eve in the US financial capital for 55 years. The National Weather Service warned that temperatures could fall to 14 degrees Fahrenheit (-10 Celsius) at midnight on December 31, the coldest since 1962. Mariah Carey, pop singer Nick Jonas and the former Fifth Harmony vocalist Camila Cabello are set to provide the entertainment at this year’s Times Square New Year’s Eve party.