South and North Korean warships exchanged fire off their western coast after the North's vessel crossed a disputed sea border and ignored several warning shots, the Joint Chiefs of Staff said in Seoul. The North Korean vessel ventured 1.3 kilometers (0.8 miles) into waters claimed by South Korea at about 10:33 a.m. local time today, triggering an exchange of fire, according to an e- mailed statement. The ship returned across the border after it was badly damaged in the exchange, Yonhap News reported, citing a government official in Seoul it didn't identify.

World leaders have hailed the fall of the Berlin Wall in celebrations marking the 20th anniversary of the upheaval that transformed Europe. German Chancellor Angela Merkel was joined at the Brandenburg Gate by Russia's Dmitry Medvedev, France's Nicolas Sarkozy and UK PM Gordon Brown.

US President Barack Obama has hailed as "historic" the approval of a health bill by the House of Representatives. He said he was "absolutely confident" the Senate would pass its own version, and that healthcare reforms would become law by the end of the year.

President Obama, extending condolences to the community at Fort Hood, Texas, reminded Americans on Saturday that people of "every race, faith and station" serve in the military — an oblique attempt to prevent a backlash against Muslims in the wake of Thursday's shootings by an Army psychiatrist.

Gordon Brown today denounced the Afghan government as corrupt and warned the president, Hamid Karzai, that he would lose international support if he failed to improve its performance. In a speech to the Royal College of Defence Studies, the prime minister said he was "not prepared to put the lives of British men and women in harm's way for a government that does not stand up against corruption".