AP - One Metro transit train smashed into the rear of another at the height of Washington's Monday evening rush hour, killing at least four people and injuring scores of others as cars of the trailing train jackknifed into the air and fell atop the first.

AP - Riot police cracked down anew on demonstrators in Iran's capital on Monday hours after the feared Revolutionary Guard threatened to crush any further post-election protests. A witness described an "air of sadness" marked by people wailing prayers into the night.

AP - Lamenting his first teenage cigarette, President Barack Obama ruefully admitted on Monday that he's spent his adult life fighting the habit. Then he signed the nation's toughest anti-smoking law, aiming to keep thousands of other teens from getting hooked.