Dallas, Texas officials said, because computer hackers, Dallas emergency alert system for all calls at night for about 90 minutes, which is by far the largest-scale alert system-incursions.

US Central time Friday at 11:42 (Beijing time Saturday, at 1:42 P.M.), 156 sirens of Dallas suddenly started, generally appears warning if tornadoes and other severe weather. Alert until 1:17 A.M. until the next day, when engineers Manual turn off alarm and relay of radio systems.

Director of the city emergency management luoke·Wazi (Rocky Vaz), said: "as of right now, we can tell you in a responsible manner, it was from an external system, activates the alarm. "Watts quoted security experts as saying that the intrusion event is an emergency alert system affected one of the biggest, most intrusions are only 1 or 2 alarm is activated. He also said: "this kind of accident is extremely rare. ”

Engineers are working to restart the system, and expected later Sunday to recover. Watts said the alarm system before restoring, Dallas will be through the local media, emergency 911 calls, Federal Radio warning system to provide services.

Watts said, system engineers are investigating the invasion, they also had contact with the FCC, but police have not been involved. Watts said the system cycle alarm 15 times before closing, each lasting 90 seconds.

美国德克萨斯州达拉斯市官员称，由于电脑黑客入侵，达拉斯所有紧急警报系统在夜里鸣叫了90分钟左右，这是至今出现的最大规模警报系统入侵事故。

美国中区时间周五晚上11点42分（北京时间周六下午1点42分），达拉斯156个警报器突然启动，一般来说出现龙卷风及其它恶劣天气时才会预警。警报直到次日凌晨1点17分才解除，当时工程师手动关闭警报器无线电系统和中继器。

城市应急管理主任罗克·瓦兹（Rocky Vaz）表示：“就目前而言，我们可以很负责任地告诉你，有人从外部入侵系统，激活了警报器。”瓦兹援引安全专家的话称，本次入侵事件是紧急警报系统受影响最大的一次，大多数入侵只会激活1个或者2个警报器。他还说：“这样的事故极为罕见。”

工程师正在重启系统，预计周日晚些时候就能恢复。瓦兹称，在警报系统恢复之前，达拉斯将会通过本地媒体、紧急911电话、联邦无线电警报系统提供服务。

瓦兹还说，系统工程师正在调查入侵事件，他们还与FCC接触过，不过目前警方还没有介入。瓦兹说，系统关闭之前循环报警15次，每次持续90秒。