A US Defense Department computer system called SIPRNet went out of commission last month at Creech Air Force Base, which houses a key drone flight center.
The cause of the problem at the Nevada base is currently unknown, according to Buzzfeed News, which was the first to report the incident Wednesday. That means anything from technical failures to hackers could be behind the system's downtime. The US Air Force posted notice of the outage last week on the FBO.gov website that lists government contracting opportunities.
Seeking bids for technical help, the posting describes a computer system on the edge of another collapse.
"The services were somewhat restored with the use of multiple less powerful devices," the posting states. "This temporary solution stabilized the services, but will not be able to maintain the demand for very long."
SIPRNet, which stands for Secret Internet Protocol Router Network, is a network that runs parallel to the internet and allows the transmission of classified data. An Air Force spokeswoman confirmed the outage to Buzzfeed and told the publication the outage was not related to drone targeting malfunctions that occurred around the same time and led to civilian deaths in Afghanistan and other lethal mistakes.
The Air Force office of public affairs didn't immediately respond to CNET's request for comment.
The base, along with Nellis Air Force Base, also in Nevada, are up for an inspection from the US Cyber Command, an arm of the military responsible for defending US computer systems and developing the ability to hack those of other countries.