Washington(CNN) Individuals who intentionally spread the novel coronavirus could be charged with terrorism for the "purposeful exposure and infection of others," a Justice Department memo says.

Writing that the virus "appears to meet the statutory definition of a 'biological agent,' " Deputy Attorney General Jeffrey Rosen said in the memo to federal law enforcement agencies and US attorneys Tuesday that "such acts potentially could implicate the Nation's terrorism-related statutes."

"Threats or attempts to use COVID-19 as a weapon against Americans will not be tolerated," Rosen said.

The memo underscores the aggressive steps the federal government is willing to consider -- and enact -- as the outbreak spreads across the country. The US has more than 64,000 cases of the virus and nearly 900 people have died as of Wednesday afternoon, according to CNN's tally.

"We must do the best we can to protect Americans' rights and safety in this novel and troubling time," Rosen said.

The deputy attorney general also detailed a "wide range of fraudulent and criminal" reported schemes related to the pandemic, including robocalls making fraudulent offers to sell respirator masks with no intent of delivery and fake coronavirus apps and websites that install malware.

"Capitalizing on this crisis to reap illicit profits or otherwise preying on Americans is reprehensible and will not be tolerated," Rosen wrote.

His memo comes after Attorney General William Barr directed federal prosecutors last week to prioritize investigations of fraudsters and hackers exploiting the pandemic.

In that memo sent to US attorneys nationwide, Barr cited reports of fake cures for the virus being sold online and email scams from people posing as public health officials as crimes that "cannot be tolerated."

"The pandemic is dangerous enough without wrongdoers seeking to profit from public panic and this sort of conduct cannot be tolerated," Barr wrote. "It is essential that the Department of Justice remain vigilant in detecting, investigating, and prosecuting wrongdoing related to the crisis."

Barr also said the "critical mission" of the Justice Department will continue as the virus shuts down other pillars of American society.

"We will ensure that the Department's law enforcement functions operate effectively during this outbreak. It is vital that we work together to safeguard our justice system and thus the safety and security of our nation," he said.