Escaping sniper fire and a steady rain of artillery shells, hundreds of refugees fled from Zawiyah on Wednesday as Col.Muammar el-Gaddafi‘s loyalists fought to keep control of this strategic city — a half-hour drive from Tripoli, the capital — and its oil refinery. About 2,000 families from Zawiyah, Tripoli and other cities near the fighting on the Libyan coast passed through one rebel checkpoint on Wednesday, according to rebel officials registering the names. Cars and trucks, piled high with refrigerators and other household items, filled a road to the Nafusah Mountains. People fleeing Tripoli said there was no electricity there on Wednesday, a further sign of the toll the rebellion has taken in Colonel Gaddafi’s stronghold, where prices of basic goods have soared amid shortages.