Spanish police on Thursday arrested seven far-right activists accused of setting off an irritant gas in an attack on supporters of independence for Catalonia, leaving five people in need of medical treatment, officials said.

The group burst into a cultural center in central Madrid and set off the gas as politicians and others gathered to mark Catalonia's national day on Wednesday evening.

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.

Madrid were eliminated in dramatic fashion from the race to host the 2020 Olympic Games after the first round of voting by International Olympic Committee (IOC) members in Buenos Aires on Saturday.

Both Madrid and Istanbul were tied after the first round -- meaning Tokyo topped that round -- and it had to be put to a second decisive vote to see who went out.

Situated in sight of unstable north Africa and on the shipping route to the Middle East, Gibraltar has military and intelligence facilities that still make it a strategic asset for Britain, analysts say.

Spain ceded Gibraltar to Britain in perpetuity in 1713 following a military struggle but has since the 1960s fought to have the territory returned to Spanish sovereignty.

In the basement of Madrid's Reina Sofia museum, a giant robotic machine painstakingly scans a painting by Catalan surrealist artist Joan Miro, slowly snapping hundreds of microscopic shots.

The pictures taken by the machine, which uses infrared and ultraviolet photography, will help experts determine the condition of the 1974 oil on canvas painting called "Women, Bird in the Night" in unprecedented detail.

Oscar-winning Spanish film stars Penelope Cruz and Javier Bardem had their second child on Monday -- a girl according to Spanish media reports.

Cruz gave birth at Madrid's Ruber International hospital just to the north of the city, where Spain's Crown Princess Letizia gave birth to her two daughters, a hospital source said.

Less than four months before the IOC vote, the three cities vying for the 2020 Olympics took their campaign to a key international audience on Thursday — with each claiming to be the safest and most financially secure choice at a time of global uncertainty.

Officials from Istanbul, Madrid and Tokyo made presentations to the SportAccord conference in St. Petersburg, their first chance to pitch their bids in public to sports and Olympic officials.

Branches of the divided Syrian opposition held talks in Madrid on Monday seeking to harmonize their approach to the country's bloody civil war, their Spanish government hosts said.

The talks included Ahmed Moaz al-Khatib, who resigned last week as leader of the Syrian National Coalition, plus other members of the coalition and "various movements" of the opposition to Syria's President Bashar Assad, the Spanish foreign ministry said in a statement.

With a pumpkin for a drum, carrots for flutes and turnips for trumpets, musicians from Vienna transformed the fresh goods in a Madrid market into honking, whistling instruments on Monday.

Visiting members of the Vienna Vegetable Orchestra marked the centenary of the San Miguel market in the center of the Spanish capital by taking saws and drills to its vegetables, coring and boring holes in them to make wind instruments.

Rafael Nadal and Serena Williams firmed up their credentials as French Open favorites by sweeping to victory in Madrid.

Nadal eased to his fifth title in just seven tournaments since returning from a seven-month injury layoff due to tendinitis in his left knee as he beat Stanislas Wawrinka 6-2, 6-4 in little over an hour to claim his third title in the Spanish capital.