Agriculture officials in Georgia and at least 12 other states issued warnings Monday about unsolicited seed packages arriving from China that may be an invasive plant species and harmful to livestock, according to reports.

Officials said it is most important that residents do not plant or dispose of the seeds and immediately contact authorities.

Besides Georgia, the state advisories were issued in Alabama, South Carolina, Arizona, Delaware, Kansas, Kentucky, Louisiana, Ohio, Tennessee, Utah, Virginia and Washington, according to reports.

Georgia’s warning was issued by Georgia Department of Agriculture Commissioner Gary W. Black after several residents reported receiving the packages by mail, according to a statement from the department’s office of communication.

The outside packaging reportedly contains Chinese writing and could be labeled as jewelry.

Officials with the South Carolina Department of Agriculture and Clemson University’s Regulatory Services division are planning to coordinate a national investigation with the U.S. Department of Agriculture’s Animal Plant Health Inspection Service.

“At this time, we are not sure what the seeds are and therefore are urging everyone to be exceedingly vigilant,” Black said. “If you have received one of these packages in the mail, please use extreme caution by not touching the contents and securing the package in a plastic bag.”

Carolee Bull, a professor who leads the department of plant pathology and environmental microbiology at Penn State University, called the alarm palpable.

“The reason that people are concerned is — especially if the seed is the seed of a similar crop that is grown for income and food, or food for animals — that there may be plant pathogens or insects that are harbored in the seed,” she told The New York Times.

Officials elsewhere said they suspect the packages to be a textbook case of agricultural smuggling.

Police in Whitehouse, Ohio, where a resident reported receiving seeds, said the packages appeared to be a part of a “brushing” fraud, according to The New York Times.

“A brushing scam,” the department said on its Facebook page, “is an exploit by a vendor used to bolster product ratings and increase visibility online by shipping an inexpensive product to an unwitting receiver and then submitting positive reviews on the receiver’s behalf under the guise of a verified owner.”

“We urge all residents to be on the lookout for similar packages. These seeds could be invasive or be harmful to livestock,” said Alabama Commissioner of Agriculture and Industries Rick Pate.

Invasive species wreak havoc on the environment, displace or destroy native plants and insects, and severely damage crops.

Anyone who has received seeds from China or any other country is urged to contact the GDA Seed Lab at 229-386-3145 or email SeedLab@agr.georgia.gov.

Tensions have heated up between Washington and Beijing in recent days as the world’s biggest economies have both shuttered consulates in Houston and Chengdu in disputes over alleged technology theft, national security, human rights and trade.

The U.S. alleged that the Houston consulate was a nest of Chinese spies who tried to steal data from facilities in Texas, including the Texas A&M medical system and the University of Texas MD Anderson Cancer Center in Houston. China said the allegations were “malicious slander.”

China maintains consulates in San Francisco, Los Angeles, Chicago and New York in addition to its embassy in Washington.

The U.S. has four other consulates in China and an embassy in Beijing, keeping the sides in parity in terms of diplomatic missions.

— This is a breaking news story. Please stay with AJC.com for the latest developments. Information provided by The New York Times was used to supplement this report.