Investigators from the Business Limitations Authority raided the offices of the three main gas companies yesterday - Paz, Delek, and Sonol. They confiscated papers relating to the sudden imposition of a one-shekel service fee on all fill-ups. The fee was introduced simultaneously by all three companies last month; until then, all companies charged a nightly service fee of approximately one shekel; as of April 1, a daily fee of 1-1.2 shekels was introduced, and the nightly fee was raised to 2 shekels. The companies say they were forced to charge the fee because of continuing erosion of their profits, due to lack of updating of the prices they may charge, and because of the raise in the minimum wage. The company heads will meet today with National Infrastructures Minister Avigdor Lieberman, who is expected to demand that they cancel the charge.