Baku, April 15, AZERTAC At least three people were killed after a helicopter crashed south of Mexico City, local authorities said Sunday, according to Xinhua.Pablo Vazquez, head of the secretariat of citizen security of Mexico City, said on social media that people in the neighborhood were not at risk after the crash."We can confirm that three people lost their lives, the pilot of the plane and two passengers," the local official said in a statement."We are crossing information to determine the identity of the three people," he added.Emergency services are still investigating the accident, which was brought under control almost immediately, Vazquez said.