Pennsylvania statewide 911 outage caused by defect in operating system

We now know what caused the 911 outage across Pennsylvania earlier this month.

According to Pennsylvania's Emergency Management Agency, the intermittent outages were caused by a defect in an operating system.

The outage lasted several hours and is not believed to be the result of a cyber attack.

The issues were first detected in Delaware County on July 11, when some calls to 911 weren't being delivered to the communications center.