It sounds easy: dispatch naval to storm a hijacked cargo ship, shoot or capture the ragtag band of pirates and free the hostage crew. But experts warn such a rescue attempt would be extremely risky.

•  Comment
•  Photos

• Red Sea nations seek to blunt waves of pirates
• Islamists say they'll fight Somali pirates

Vanishing Arctic sea ice brought on by climate change is causing the crucially important microscopic marine plants called phytoplankton to bloom and die away as never before. David Perlman

China acknowledged for the first time that more than 19,000 children were among the dead in the huge earthquake that hit Sichuan province in May.

• U.S. warned of Chinese spying on computers, space

The CIA repeatedly misled Congress and the Justice Department in their investigations of the 2001 shoot-down of a Peruvian plane carrying U.S. missionaries, according to an internal CIA probe.