CHRISTCHURCH: Residents help a driver to free his car stuck in a liquefaction sink hole after a 5.8-magnitude quake struck north of Christchurch, New Zealand, Friday Dec. 23, 2011. A series of strong earthquakes struck Christchurch on Friday, rattling buildings, sending goods tumbling from shelves and prompting terrified holiday shoppers to flee into the streets. There was no tsunami alert issued and the city appeared to have been spared major damage.AP/PTI(AP12_23_2011_000054B)