Hundreds of thousands of Catalans will unite to create a 400-kilometer (250-mile) human chain on September 11, part of a spectacular campaign for independence fiercely opposed by Madrid.

Some 400,000 people aim to join hands along the entire coastline of the northeastern region of Catalonia to demand an historic redrawing of the map of Spain.

A top critic of President Vladimir Putin on Sunday faced a Kremlin-backed incumbent in a hotly contested Moscow mayoral poll, the first time an opposition leader has been allowed to stand in a high-profile election.

In the Russian capital's first mayoral election in a decade, Muscovites had to choose from six candidates including current pro-Kremlin mayor Sergei Sobyanin and main opposition candidate Alexei Navalny.

Egyptian and Syrian drug traffickers set fire to their ship carrying more than 30 tons of hashish before being arrested by Italian police in the central Mediterranean, police said Saturday.

Italian drug busters had been tipped off "three days ago that a major drug shipment was being transported on the cargo ship en route in the Mediterranean", Italian police said in a statement.

Waving signs and placards, some 200 protesters gathered at the White House Saturday before marching to Capitol Hill, in a demonstration opposing possible U.S. military strikes against Syria.

The midday rally was one of several planned in cities across the United States Saturday and ahead of larger planned protest in Washington on Monday.

Thousands took to the streets in Berlin Saturday in protests against Internet surveillance activities by the U.S. National Security Agency and other intelligence agencies, and the German government's perceived lax reaction to them.

Organizers, among them the opposition Greens, The Left and Pirates parties, said 20,000 people turned out. Police would not confirm the figure, saying only their "tally differs from that of the organizers".

Lorena was downgraded from a tropical storm to a tropical depression Saturday as it swirled off the coast of Mexico near the Baja California peninsula.

The storm has dumped heavy rain on the region and had prompted authorities to prepare shelters for the evacuation of 30,000 people from the resort of Los Cabos.

The Taliban said on Saturday they had released an Afghan female MP held hostage since August 10 in exchange for six prisoners who were relatives of their fighters.

An Afghan provincial governor later confirmed the release but added no further details.

More than 100 protesters interrupted a military parade in Rio Saturday held to mark Brazil's independence day and were dispersed with teargas.

Five people were injured and taken to the hospital, civil police said, adding that at least 10 protesters were arrested.

Outgoing Pakistan President Asif Ali Zardari said in comments aired Saturday he will not seek to become prime minister and will instead focus on leading his party after stepping down.

Zardari, co-chairman of the Pakistan's Peoples Party (PPP), vacates the presidency on Sunday and will be replaced the following day by Mamnoon Hussain, a businessman and close ally of Prime Minister Nawaz Sharif.

Prime Minister Kevin Rudd on Saturday conceded defeat to conservative challenger Tony Abbott in Australian elections and said he will step down as Labor leader as voters punished the party for internal warfare.

Some 100 minutes after the polls closed, Rudd mounted the stage in a function room at the Gabba cricket ground in Brisbane to wish his rival well in the "high strain" lifestyle that comes with the leadership.