Illegal drugs are more expensive and difficult to obtain worldwide due to the COVID-19 pandemic, according to a new report by the United Nations Office on Drugs and Crime (UNODC).

The pandemic has led to border controls, lockdowns and flight shortages that are affecting the flow of illegal drugs, Reuters reports.

According to the report, restrictions resulting from lockdown could hinder the production of opiates in Afghanistan. Due to the pandemic, workers might not be able or willing to travel to areas where opium poppy is grown in the country, which could affect this year’s harvest, UNODC said. A shortage of heroin supply could lead to an increase in people switching to fentanyl and its derivatives, the report noted.

An increase in the use of pharmaceutical products such as benzodiazepines has also been reported, already doubling their price in certain areas, according to UNODC. “Another harmful pattern resulting from drug shortages is the increase in injecting drug use and the sharing of injecting equipment–all of which carry the risk of spreading diseases like HIV/AIDS, hepatitis C, and COVID-19 itself,” the report stated.