Earlier this week, worrying reports from several OnePlus 5 owners noted that the device would reboot whenever 911 was dialled on the device. To their credit, the Chinese company has acted swiftly, with an impending update for the flagship phone set to rollout to devices in coming days.  

The precise cause of the reboot error has not been disclosed by OnePlus, with it originally brought to people's attention via Reddit, with a commenter noting the issue occurring twice when trying to report a burning building. 

I had to dial 911 on my OP5 yesterday (saw a building on fire a few blocks away) and both times I tried my phone rebooted on me. from oneplus

Needless to say, this is less than ideal, and in some cases could have proved extremely dangerous if not discovered as early as it was. The original Redditor who made the posting has since tested out an OTA update and says the issue has been resolved.