sentences:  In March 1974, only 100 civilian technicians remained to operate the residual communications facility, along with their families, and eight to ten U.S. military personnel.On the night of January 31, 1975, heavy fighting broke out in Eritrea and incoming rocket-propelled grenades landed inside the Tract E compound.This began a season of frequent nighttime firefights between the Eritrean resistance and the Soviet-backed Ethiopian forces.