Eventually the prisoners felt they could no longer dump sand above ground because the Germans became too efficient at catching them doing it. After "Dick"'s planned exit point was covered by a new camp expansion, the decision was made to start filling it up. As the tunnel's entrance was very well-hidden, "Dick" was also used as a storage room for items such as maps, postage stamps, forged travel permits, compasses and clothing. Some guards cooperated by supplying railway timetables, maps and many official papers so that they could be forged. Some genuine civilian clothes were obtained by bribing German staff with cigarettes, coffee or chocolate. These were used by escaping prisoners to travel from the camp more easily, especially by train.