Officials in the North Dakota Department of Agriculture have received several reports of North Dakota residents receiving mysterious seeds in the mail from China, unsolicited.

“We’re not sure why these seeds are being sent or what the motives are behind this,” Agriculture Commissioner Doug Goehring said.

Residents across the country have reported receiving the seeds, and at least 28 states have issued warnings about them.

Residents of the state who receive such a package are urged to retain the seeds and packaging, including the mailing label; do not plant the seeds; contact the department of agriculture at 701-328-2391 or email their name, phone number and number of packages received to doa-phytos@nd.gov; then await further instructions.

Steve Sebesta, deputy seed commissioner for the North Dakota State Seed Department, said that although potential dangers of simply throwing the seeds away are probably limited, it's best if recipients contact the department of agriculture.

"You don't know where household trash ends up," he said. If it goes into a landfill, for example, that seed may not be buried deep enough to prevent it from germinating and potentially spreading that way."

Most importantly, he said, is to not plant them.

"That's potentially the worst thing they could do ... because the seed was unregulated, and it did not go through the customary US Customs program ... we have no idea whether or not those seeds are potentially an invasive species or whether they might have a plant pathogen that would be not already existing in the state or the United States."

"The biggest problem with that would be the potential unregulated release of a pest species, whether that's a plant species that's not known to exist here and could potentially be invasive or harm the environment, North Dakota agriculture and our food supply," he said. "A good example of that would be kudzu in the southeast part of the United States. It's just taken over a lot of that land."

Kudzu is a plant native to Asia that was introduced to the US in the late 1800s. It's considered an invasive species by the U.S. Department of Agriculture.