A juvenile detention center in Ohio was evacuated and seven people hospitalized after fentanyl gas was released through the air vents. Jeff Lehman, chief deputy for the Williams County Sheriff’s Department, told WTVG that three corrections officers and four detainees at the Northwest Ohio Juvenile Detention Training and Rehabilitation Center had been taken to hospital after falling ill, but all were expected to be OK. Investigators are trying to work out how the gas was released. Fentanyl is used as an anesthetic but can be fatal in high doses. It is believed to be the gas used by Russian authorities in a disastrous attempt to break a Moscow theater siege by Chechen terrorists in 2002, which ended with the deaths of at least 170 people.