«Links» are the members who transfer instructions and other information from one level in the organization to another, such as from a city leader to a zone leader, a zone leader to a cell, or from a leader of the organization to the person in charge of explosives. These have to be tested members with a high level of political consciousness and stability and a knowledge of security measures, secrecy and countersurveillance. There are many kinds of contacts but certain rules apply to all – they should be be the same at each level (for example, regional leaders have the same kind of contacts), they should be hierarchical (for example, a regional leader should not come into contact with the member of a cell). They should be continual and regular. This does not mean they should occur at the same time and place, but according to the requirements, a number of contacts per week or month are scheduled; this schedule is adhered to even if there are no jobs to be done or information to share. The organization should have a reserve of contacts in the event that a member or a place is discovered. Personal contacts. These generally require caution, as they are the most dangerous. They can take the form of interviews, visual contact or a «pass.» An interview is when we talk to a comrade, while visual contact occurs without exchanging words, one of the people involved might not know that contact has been made. For example, to ensure that a comrade has arrived or passed by somewhere, we place one or more comrades at various points on his route to find out whether the mission was completed or whether he was followed. A «pass» is the kind of personal contact that has to be perfectly timed and involves detailed preparation, as well as a careful choice of place. We use this type of contact to give a member written instructions, information or material. For example, pretending to be browsing in a bookshop, Comrade A opens a book at 10.15 a.m. and places a piece of paper bearing instructions inside it and puts it back in its place. At 10.17 a.m., Comrade B opens the same book, takes the paper and leaves. A also leaves, having ensured that B has the paper. Contacts are chosen by the cell leader on the basis of proposals or reports from cell members. The cell member makes proposals for various contacts and the cell leader chooses those he feels are suitable on the basis of a report including place, time, covers (for both comrades) suitable for the place and time, passwords (one for aborting the mission, or aborting in favor of a reserve), identifying characteristics (if the two do not know each other), and members’ movements. When members do not know each other, the next person up in the hierarchy identifies them. These contacts require great precision and discipline. A member who sets out to make a contact must have determined the route in advance, the points of countersurveillance, and places to evade a possible «shadow.» He needs to set out at least one or two hours ahead of time. When he arrives at the contact point, he should check to see if he or the other person is being followed. When contact is made, the first thing to do is to remind the other person of the covers and to determine the next contact. Then they can discuss organizational issues. At the end it is a good idea to ask personal questions, because one or the other might be having family or work problems and need help. When the contact is over, each member is to follow a predetermined route and to remain vigilant. At every contact there should be a reserve. If a member does not arrive, then there should be a reserve contact, who should be different each time. Finally, there should be an «emergency» contact for when something important happens. This can remain the same until it is used. Contacts between two members of the City Organization conspiracy are very dangerous. Police might arrest members coming into contact as well as intercepting the message they are bearing. Therefore, contacts of this nature should be restricted to a minimum, be effective and all regulations should be strictly followed. Non-personal contacts In these types of contacts, what is most important is the choice of place (or person) and naturally a knowledge of «urban situation tactics.» These non-personal contacts are hiding places, post offices, key words and invisible ink. Hiding places. These can be used for material to be picked up by someone else in the near or distant future, such as storerooms, the size of which should be referred to in the report. These should not be abandoned cars, which are likely to be towed away at any time, and the hiding places should make for easy delivery and collection of material. The site should be described in great detail, including the covers of the people delivering and collecting the material, the best hours to use it, the length of time an object can be left there, any special conditions required to keep it in good condition (such as plastic wrap or a metal crate). In choosing a hiding place, we must take care there are no children playing nearby who might discover it, that public works are not being carried out nearby, even the presence of animals such as mice that could destroy the wrapping. It is a good idea to test the hiding place by hiding something of value there, such as money, for a while. As hiding places can be toilets in cafes, shelves in stores, as «passes» where the members will not come into personal contact, the time and moves have to be precise. Post offices. These are people sympathetic to the cause who offer to transport material, notes or letters from one member to another. These people must be absolutely trustworthy. The members need not know their names, if this is possible, and the «post offices» must not know the names of the people they are providing the link for. Codes. These are words, numbers, objects with a special significance indicating specific objects, information or instructions that cannot be mentioned by name. Agreement is reached, for example, to refer to weapons as «cigarettes» in a letter or contact. A grocery bill reading «3 kilos of rice, 1 kilo of sugar, 2.5 kilos of beans,» can mean three weapons, one bomb and 25 detonators. Invisible ink. We use chemical compounds or simple substances such as lemon or milk. This method is not recommended, however, as the police are experienced and have very good laboratories for detecting it. One or more officers can follow someone, according to police capabilities. They always observe three rules – anonymity, effectiveness and continuity, in the sense that they must not lose sight of their prey for a second. They always try to hide their faces from the person they are following and, in general, try to remain unobtrusive. They often break the rule of anonymity in order to maintain effectiveness and continuity.