BAGHDAD — Motorcycle bombs killed at least 20 people in separate attacks in Baghdad yesterday, at least 19 of them in a crowded bazaar, part of an apparent trend toward increased use of motorcycles to thwart stepped-up security measures.

The attacks were the latest in a week of violence that has killed more than 250 people, with just four days to go before the deadline for U.S. combat troops to withdraw from cities. The spike has raised fresh doubts about the ability of Iraqi forces to provide security and fight a stubborn insurgency as their U.S. partners become less visible.

U.S. and Iraqi officials have warned they expect more violence in the days surrounding the deadline as militants stage a show of force to try to stoke sectarian bloodshed and undermine confidence in the government.

U.N. A 'CENTRAL FORUM' ON ECONOMIC CRISIS

UNITED NATIONS — More than 140 countries agreed yesterday on a blueprint giving the U.N. a new role representing developing countries hit hard by the world's worst economic crisis in 70 years.

The 15-page document, which is not legally binding, makes clear that a solution to the economic crisis must include the views of all 192 U.N. member states and cannot be left just to the Group of Eight major industrialized nations or the Group of 20 key countries that account for more than 80 percent of the global economy.

General Assembly President Miguel D'Escoto Brockmann called the document "a great achievement" adding, "the G192 has now been established as a central forum for the discussion of world financial and economic issues."

DETROIT COUNCILWOMAN GUILTY OF BRIBERY

DETROIT — City Councilwoman Monica Conyers pleaded guilty to bribery charges yesterday, becoming the latest Detroit politician taken down by scandal and marking a victory for federal prosecutors in their nearly two-year investigation into city corruption.

Conyers, the wife of powerful Democratic congressman John Conyers who won her seat in 2005 largely on her popular husband's name, admitted in federal court to taking cash from a Houston-based company in exchange for her vote on a city sludge-treatment contract.

The normally fiery Conyers, 44, spoke quietly while entering her plea in federal court, and left the courthouse without commenting to reporters, free on bond. She faces up to five years in prison and a $250,000 fine.

TRACTOR-TRAILER CRASH IN OKLAHOMA KILLS 9

MIAMI, Okla. — At least nine people died yesterday when a tractor-trailer slammed into a line of cars stopped on a northeast Oklahoma turnpike by an earlier accident, leaving twisted metal and debris strewn on the highway and stranding miles of traffic in scorching heat for hours.

Emergency crews worked well into the evening to untangle the wreckage and determine whether there were additional victims.

Oklahoma Highway Patrol Lt. George Brown said traffic was stopped about 1 p.m. on the Will Rogers Turnpike northeast of Miami because of an earlier crash when the big rig slammed into at least three cars, which then crashed into more vehicles.

ALLEGED HIT MEN, POLICE CLASH IN MEXICO

MEXICO CITY — A shootout between police and suspected cartel hit men in central Mexico yesterday left at least 12 people dead and one police officer wounded, officials said. Guanajuato state Attorney General Carlos Zamarripa said police and soldiers were checking a report of armed men at a building in the town of Apaseo el Alto when assailants opened fire and lobbed grenades at them.

Mexico is suffering a wave of gang violence that has killed more than 10,800 people since President Felipe Calderon took office in December 2006 and launched a military-led crackdown on drug traffickers.

MAN BITTEN BY SHARK AT AUSTRALIAN BEACH

A man was attacked by a shark while surfing at a beach south of Sydney early today, Australian authorities said.

The surfer was bitten at Seven Mile Beach south of the town of Kiama at about 8:45 a.m. local time, said Les Majoros, a spokesman for the New South Wales state ambulance service. The man suffered a laceration to his lower leg and was transported to a hospital, where he is in stable condition, Majoros said by phone.

In the first three months of the year, eight people were bitten in or outside Sydney, prompting the state government to announce plans to tag captured great white sharks and monitor their movements in response to "community concern."