The Department of Defense plans to shut off employee access to streaming services like Alphabet Inc.’s YouTube on Monday when employees are connected to the Pentagon’s network, as the shift to working from home amid the spread of COVID-19 stresses computer infrastructure.

During a town hall meeting on Monday, Chief Information Officer Essye Miller said nonessential Department of Defense employee usage of streaming services like the Google GOOGL, -2.41% GOOG, -2.37% video-sharing site was already putting strain on the organization’s network. The DoD employs 1.3 million active-duty service members, 826,000 National Guard and Reservists, and more than 732,000 civilians.

“Given the increased telework demand, we’ve seen a tremendous increase on the network, unprecedented demand just over the last weekend or so,” Miller said. “As such, we’re taking actions, shutting down YouTube effective tonight.”

Miller also said that other video-streaming services would have bandwidth lessened on the network, known as throttling, and music-streaming services like Sirius XM Holdings Inc.’s SIRI, -2.82% Pandora Music would only be for tasks deemed essential.

“We will start throttling streaming services today,” Miller said. “We’re seeing increased use on things like Pandora and other streaming music services. We ask that use of these services are not mission-essential, that you refrain from using them on the DoD network.”

Allowing a large number of employees to work remotely when they are accustomed to working at the office poses a security and bandwidth challenge for many organizations, according to security professional who recently spoke with MarketWatch. Servers trying to process a large amount of outside traffic can be overwhelmed easily if employers do not want their employees using an unsecured internet connection, and being able to accommodate that sort of volume can get expensive, Chenxi Wang, managing partner at Rain Capital, said in a recent interview.

For more: Working from home because of coronavirus? Don’t give your company a different kind of virus

Miller also acknowledged that with more DoD employees working from home, the DoD’s attack surface just got that much bigger for cybercriminals and hackers, and urged employees to be more vigilant. A request for further comment from the Department of Defense Requests was still outstanding when this story was published.

“With the increased telework capability comes an increased attack surface for our adversary,” Miller said. “They’re already taking advantage of the situation and the environment that we have on hand.”

“Cybersecurity while teleworking is especially important and requires extra effort and vigilance,” the DoD told workers in online guidance. “That is because some of the inherent security measures that we take for granted while working directly within a DoD network may not be fully articulated while working remotely at home.”

“For this reason, DoD personnel need to be especially alert and attentive to cyberattacks, malware, phishing expeditions, network security protocols, encryptions requirements, et al, which may threaten government information stored on telework devices and transmitted across external networks.”

See also: Hackers are using coronavirus concerns to trick you, cybersecurity pros warn

Last week, congress’s Cyberspace Solarium Commission released a report that said the nation’s computer infrastructure was particularly vulnerable to attack.

“The United States now operates in a cyber landscape that requires a level of data security, resilience, and trustworthiness that neither the U.S. government nor the private sector alone is currently equipped to provide,” according to the report.

“Moreover, shortfalls in agility, technical expertise, and unity of effort, both within the U.S. government and between the public and private sectors, are growing.”

Hackers are already taking advantage of the scramble to contain coronavirus, attempting to attack systems at the U.S. Department of Health and Human Services late Sunday, according to a story first reported by Bloomberg News.

HHS has yet to respond to a MarketWatch request for comment.

Read:Stocks sink 9% as investors await U.S. government response after Fed historic action fails to bring calm