In prisons, despite strict surveillance, prisoners may still obtain drugs through a variety of channels. Here are some common channels: 1. **Smugglers and external assistance**: - **Visitors and family members**: Some relatives and friends of prisoners may bring drugs when visiting, take them orally or hide them in their belongings. - **Illegal mail and packages**: Drugs may be hidden in letters, packages or other mailed items and transported into prisons. 2. **Prison staff**: - **Internal corruption**: Individual prison staff may provide drugs to prisoners through bribery or other illegal means. - **Supervision loopholes**: In some prisons, inadequate supervision or loopholes make it easier for staff to smuggle drugs. 3. **Self-made and internal production**: - **Self-made drugs**: Prisoners may use limited resources in prison to make simple drugs such as methamphetamine (ice) or marijuana. - **Plant cultivation**: Some prisoners will secretly grow marijuana or other plants that can be used to make drugs in prison. 4. **Cooperation and trading**: - **Black market in prison**: Prisoners may obtain drugs through secret transactions and establish internal supply and demand networks. - **Exchange of other items**: Drugs may be used as a means of exchange for other goods or services within the prison. 5. **Electronic equipment and communications**: - **Covered communications**: Using mobile phones or other electronic devices to contact the outside world to receive drugs or instruct the delivery of drugs. - **Encrypted information**: Using secret codes or signals to transmit information about drug acquisition. 6. **Concealment of items**: - **Hidden places**: Using hidden places in prison facilities, such as cracks in walls, inside furniture, or under beds, to store and hide drugs. - **Personal items**: Hiding drugs in clothing, shoes, hair, or other personal items. **Response measures**: In order to curb the drug problem in prisons, many prisons have taken a variety of measures, including strengthening security checks, monitoring communication equipment, training staff to identify and respond to drug smuggling, and providing drug treatment and rehabilitation programs to help prisoners quit drug addiction. Prison administrations and law enforcement agencies need to continue to work together and adopt a comprehensive strategy to reduce the circulation of drugs in prisons and protect the health of prisoners and the safety of prisons.