RIO DE JANEIRO (AFP) - Brazil will put a 10,000-strong elite security force on standby at the World Cup to prevent a repeat of the disorder that marred last year's Confederations Cup, the justice ministry said Friday.

The government has warned it will not tolerate protests like those in June last year that saw more than a million people demonstrating in several cities against corruption and what critics say is the astronomical cost of staging the World Cup, which starts on June 12.

Protesters have vowed to target the tournament this summer, when an estimated 600,000 foreign fans and about three million Brazilians will criss-cross the continent-sized nation of some 200 million people.

Organisers are also mindful of football-related violence of the kind which shocked Brazil last month when four fans were hurt in running battles between supporters of Atletico Paranaense and Vasco da Gama at a top-flight match.

A military police colonel will coordinate the 10,000 special force, which comprises military and civil police, firefighters and logistics experts.

"They will shore up security in the 12 venue cities and have clearly defined functions to back up the police," a justice ministry spokesman told AFP.

The contingency force has been dubbed a "shock troop" by the Globo newspaper.

A precise security plan is being drawn up and the blueprint should be finalized by the end of this month, the ministry said.

The 10,000 members will have undergone more than two years of training by the time of the opening match of the World Cup in Sao Paulo, when the hosts - five-times champions - play Croatia.

Football's governing body FIFA has insisted that "a very comprehensive security concept," much more sophisticated than that seen at Brazilian league games, will be in place for the World Cup.

"The troop is not an ordinary force. We are only drafted in times of crisis, only for specific missions," Globo quoted Colonel Alexandre Augusto Aragon as saying. "We shall be able to act simultaneously in the 12 venues."