Near a cluster of purple petunias in a Thousand Oaks greenhouse sprouts a key weapon in the nation’s ambitious push into biofuels.

SAN FRANCISCO — Thousands of marchers, angry but energized by a sense of growing support for their cause, closed down a major downtown thoroughfare Sunday in a largely peaceful display of opposition to the Iraq war.

WASHINGTON  — The Senate Judiciary Committee chairman said Sunday he intends to subpoena White House officials involved in ousting federal prosecutors and is dismissing anything short of their testimony in public.

BAGHDAD — Sunni insurgents, resilient despite the five-week security crackdown in the capital, killed at least six more U.S. troops over the weekend. A Sunni car bomber hit a largely Shiite district in the capital Sunday, killing at least eight people.

WASHINGTON — An Army contract to privatize maintenance at Walter Reed Medical Center was delayed more than three years amid bureaucratic bickering and legal squabbles that led to staff shortages and a hospital in disarray just as the number of severely wounded soldiers from Iraq and Afghanistan was rising rapidly.

WASHINGTON — Sen. Hillary Rodham Clinton, D-N.Y., posts regular “HillCasts” to talk about her positions on equal pay, health care and Iraq.

SAN LEANDRO — A federal politician who publicly acknowledged last week that he doesn’t believe in God appears to enjoy healthy support among constituents.

CHILTON, Wis. — A man who spent 18 years in prison for a rape he didn’t commit was convicted Sunday of murdering a photographer, whose charred bones were found in a burn pit outside his home.

WASHINGTON — When climate scientist Andrew Weaver considers the idea of tinkering with Earth’s air, water or sunlight to fight global warming, he remembers the lessons of a favorite children’s book.

ANCHORAGE, Alaska — Two-time runner-up Ramy Brooks was disqualified from the Iditarod Trail Sled Dog Race for abusing his dogs.

SACRAMENTO — Former Assemblywoman Wilma Chan is hoping to survive the musical-chairs game created by California’s term limits and win a state Senate seat next year.