The Defense Advanced Research Projects Agency (DARPA) is researching how to genetically modify crops using virus-carrying insects.DARPA says the program could help protect crops from droughts, floods, and frost. It could also protect the US food supply from international attacks.Some scientists and lawyers, however, say they believe the Insect Allies program is uncontrollable and could be engineered to kill plants instead.Blake Bextine, Insect Allies' manager, dismissed the scientists' claims, saying researchers are including multiple emergency brakes in the system to shut the technology down if needed.A US government-funded project is studying how to genetically modify crops using virus-carrying insectsin an effort to protect the country's food supply from threats.The Defense Advanced Research Projects Agency (DARPA) started the four-year Insect Allies program in 2016 with a $45 million budget. The agency aims to arm plants with protective genes within one season, which would be much faster than changing crops through existing genetic engineering technologies that take multiple generations.As the Insect Allies program pushes forward, some scientists and lawyers have voiced concerns about the research. In an October 4statement published in the journal Science, they compared Insect Allies to biological weapons and said the program could lead to the destruction of numerous crops.Guy Reeves, a researcher at Germany's Max Planck Institute for Evolutionary Biology, told The New York Times that he finds it difficult to picture how a virus that spreads through insects could ever be controlled.You havent just released a transmissible virusyouve released a disease, Reeves told The Times. The United States knows better than to return to a biological arms race.Hours after the critics' statement was released, DARPA defended its program, which targets an "often under-appreciated element of national security." Blake Bextine, Insect Allies' manager, told The Times that the program has been transparent about its new technology.Were glad people are asking questions, Bextine told The Times. But food security is national security. It stabilizes our society.Over the past two years, scientists at a number of universities, including Pennsylvania State University and the University of Texas-Austin, have been running experiments for the project.DARPA has also invited representatives from the US Department of Agriculture, the Food and Drug Administration, and the Environmental Protection Agency to its Insect Allies meetings.DARPA hopes the new technology will let farmers grow food without worrying about losing crops due to frost, disease, droughts, floods, or attacks by other people. According to The Times, one of the crops being studied is maize, which is a vital food source for hundreds of millions of people in Africa and Latin America.The critics, however, said DARPA work could serve as a blueprint for biological weapon production if the agency makes its research findings public. Instead of helping farmers, insects could be engineered to transmit viruses that kill plants, Reeves said.The mere announcement of this program may motivate other countries to develop their own capabilities in this arenaindeed, it may have already done so," the critics wrote, saying military operations in other countries often react to competitors' actions.Critics said DARPA should focus on crop protection methods that already exist, such as aerial spraying, but the agency said this would have low precision and high costs. Bextine also told The Times that virus-carrying insects would not permanently change a plant's genome.If you see a drought coming, you can deploy the system to sustain a period of difficulty, and then go back to a natural state, Bextine told The Times. We are developing tools that are futuristic, but they are based very much in reality. This is biology we understand very well.On top of that, DARPA has asked its researchers to create at least three ways to shut the system down if needed.Reeves, however, does not believe this is enough, according to The Times.I think this project was decided down one quiet corridoran agency with intentionally little oversight that comes up with slightly crazy ideasand top people in the Pentagon will be as shocked as I was, Reeves said.SEE ALSO:Genetically modified insects may be the key to the US military's new armorJoin the conversation about this storyNOW WATCH: The 5 most extreme newborns in the animal kingdom Click here to read full news..