Originally posted by the Voice of America. Voice of America content is produced by the Voice of America, a United States federal government-sponsored entity, and is in the public domain. US Authorities Pursuing 100 Leads in Mass Killing at Nightclub by Ken Bredemeier Authorities in Orlando, Florida said Monday they are working on a hundred leads to try to determine if the suspected shooter at a gay nightclub had help in carrying out the biggest mass killing rampage in U.S. history. "There may be prosecutions down the road," Federal Bureau of Investigation agent Paul Wysopal told reporters in the southeastern U.S. city. "No stone will be left unturned." He spoke a day after officials say Omar Saddiqui Mateen, a 29-year-old American Muslim born to Afghan parents, gunned down 49 people and wounded 53 others at the Pulse bar and dance club in a middle-of-the-night assault. Authorities say that during his attack on the club, Mateen called Orlando's 911 emergency line and pledged allegiance to Islamic State and its leader, Abu Bakr al-Baghdadi, and also referenced the 2013 Boston Marathon bombing that killed three people. U.S. Attorney Lee Bentley said that others who may have had connections to Mateen are being investigated, but that there is "no reason to believe" the public may be in further danger. The FBI twice in recent years questioned Mateen about possible connections with terrorist groups but found nothing to warrant any charges. Survivors' stories Police ended the early Sunday mayhem at Pulse after three hours, shooting Mateen to death after heavily armed police tactical units raided the club, which calls itself the "hottest gay bar in Orlando." WATCH: Witness recalls club shooting ''Orlando police chief John Mina said the raid "saved many, many lives." He said one policeman was hit in the head by one of the gunman's shots, but that his Kevlar helmet saved his life. Officials said two of the gunman's weapons, including a semi-automatic rifle, were found in the club and a third located in his car. Orlando Mayor Buddy Dyer said officials have identified all but one of the 49 victims and so far have been able to reach half of their families to let them know of the deaths of their loved ones. Florida Governor Rick Scott said many of the victims were residents of Puerto Rico, a U.S. island territory off the southeastern U.S. coast and a short flight from Florida. As authorities continue to sort through the horrific, bloody scene at the club, some survivors are beginning to recount their escape from the gunman's onslaught. '' "I crawled my way outside the back exit," Christopher Hansen told CNN. "I was zig-zagging my way," hearing gunfire as he left the chaotic scene -- "boom, boom, boom." Another man at the club, Jon Alamo, said he spotted the gunman and feared for his life. "My first thought was, 'Oh my God, I'm going to die,''' Alamo said. "I was praying to God that I would live to see another day. I couldn't believe this was happening. "He was holding a big weapon," Alamo said. "He had a white shirt and he was holding the weapon ... you ever seen how Marine guys hold big weapons, shooting from left to right? That's how he was shooting at people." Alamo said he escaped by running to one of the club's smaller dance rooms, along with others who fled the gunman's fury by rushing to an area where club workers had knocked down a wooden fence to create an escape route. Mourning vigils On Sunday night, thousands of people, gay and straight, held candlelight vigils in several major cities across the U.S. for the Orlando victims. Vigils for the shooting victims were held in Orlando itself, as well as in Boston, Chicago, New York, San Francisco and Washington. WATCH: Gay Men's Chorus of Washington Sings at White House Vigil '' In Manhattan, lights on the iconic Empire State Building were turned off in sympathy for the victims. The spire at One World Trade Center - near the site of the worst terrorist attack on U.S. soil in 2001 - was lit in rainbow colors, the symbol of gay pride. President Barack Obama ordered U.S. flags to be flown at half-staff in memory of the victims. Obama declared it an act of terrorism and said the FBI is leading the investigation. He said no effort will be spared to find out what inspired the killer or if he had any links to terrorist groups. WATCH: President Obama's statement '' The grim president again addressed a stunned nation from the White House, saying it is easy for someone to get his hands on a weapon to shoot people in schools, churches, movie theaters and nightclubs. "We have to decide if that's the kind of country we want to be," he said. "And to actively do nothing is a decision as well." Secretary of Defense Ash Carter said, "If investigators conclude this was an act of terror directed or inspired by ISIL (Islamic State), it will only steel our resolve to defeat this depraved enemy, prevent the spread of its hateful ideology, and defend our people." Mateen's former wife Sitora Yusufiy said her ex-husband was bipolor. "He was mentally unstable and mentally ill," she told reporters in Boulder, Colorado. While the couple was married for two years, Yusufiy said they were only together for four months because he was abusive. A Florida gay rights group has established a crowd-funding campaign on gofundme.com to raise money for the victims and their families. Equity Florida says it is working with "a team of attorneys and experts" who have deployed money raised for victims of other U.S. massive shootings "to ensure funds are distributed correctly." More than $1 million had been raised by early Monday. __________________________________________________________________ [1]http://www.voanews.com/content/autorities-pursuing-100-leads-in-mass -killing/3373752.html References 1. http://www.voanews.com/content/autorities-pursuing-100-leads-in-mass-killing/3373752.html