. ♪ the sentra, with nissan conne[ male announcer ] tv's come a long way. from color.lat screens. now it's taking a quantum leap. introducing fios quantum tv. record up to 12 shows at the same time. store up to 200 hours of entertainment in hd. plus watch live tv anytime with the fios mobile app. redefining what tv can be. that's powerful. call the verizon center for customers with disabilities at 800.974.6006 tty/v >>> good evening. thank you for joining us. arson can be one of the toughest crimes to prove, but in phoenix one arson squad seemed to find answers few others could. arguably the best arson investigators in the nation with the numbers to back it up. but now they are under fire with some asking whether the investigators have been accusing the innocent. here is abc's byron pitts with burned, arson squad under fire. >> once the investigator gets there we take over. >> this is captain sam richardson. >> two fires today already. >> captain fred anders. they're investigators with the phoenix fire department elite arson squad taking on one of the deadliest crimes