Woo, Stu (June 13, 2016). "Orlando Nightclub Shooting Puts G4S in Spotlight Again: U.K.-based mostly protection large that utilized Omar Mateen explained its vetting had raised no purple flags". Young, Lou (June 12, 2016). "ISIS Claims Responsibility For Orlando Nightclub Attack That Left fifty Dead". Liston, Barbara (June 12, 2016). "Fifty individuals killed in massacre at Florida homosexual nightclub: police".