By Akhtar Soomro and Ariba Shahid KARACHI, July 17 (Reuters) - Relatives of the five crew members aboard a Boeing 737 cargo plane that crashed into the Arabian Sea off Pakistan last week are urging an international search effort to find the flight recorders to determine the cause. Debris from the K2 Airways freighter was recovered shortly after the July 7 crash, but the water in the area is about 3,000 m (9,800 feet) deep.
