The mission statement of the Maltese Police Force is to promote and maintain the country as a safe and secure state. It is the duty of the Police to preserve public order and peace, to prevent, detect and investigate offences, to collect evidence and to bring the offenders, whether principals or accomplices, before the judicial authorities. The fight against trafficking in illicit drugs and controlled substances, crimes against persons and crimes against property is primarily led by the Police. The District Police constitute the backbone of community policing and provide the first response whilst Specialised Branches, such as the Stolen Vehicles Section, the Forensic Lab and the Homicide Squad perform more in-depth investigations. The Police also deal with immigration issues, border control, the vetting of entrance visas, and work and residence permits. After Malta joined the Schengen Zone the Police International Relations Unit was recognised as the local contact point for police cooperation matters with other EU States.