Interpol represents NCBs in 177 countries, and each NCB is linked electronically with the others. The USNCB is divided into divisions to support investigative and managerial operations. Operational units include investigative support, alien/fugitive, criminal, drug, financial fraud, and liaison divisions. The USNCB follows the Interpol system of color-coded notices to communicate various kinds of criminal information. While the Alien/Fugitive Division has many responsibilities, its most important function is to assist U.S. law enforcement agencies in locating, identifying, and apprehending fugitives who have committed crimes in the United States and then fled to a foreign country. Law enforcement agencies are encouraged to review their files in order to identify the most serious and high-profile fugitives with some degree of international connection. The USNCB can obtain various types of investigative assistance through Interpol channels. Law enforcement agencies wanting to contact the USNCB to request assistance with an international investigation, background or applicant check, pursuit of a fugitive, or collection of evidence across international borders where compulsory process is not required are asked to submit their request through Interpol State Bureau Offices, and a list of these offices is provided.