RIO DE JANEIRO (AP) -- Six hundred additional military police will be assigned to Sunday's World Cup match at Rio's Maracana stadium between Belgium and Russia after almost 100 un-ticketed Chilean fans rampaged through the stadium's media center before the last game.
Colonel Jose Luis Castro, head of military police for Rio de Janeiro state, said Friday the reinforcements would be used to beef up the 2,500 military police that had already been assigned to the game.
''Should there be an attempt to invade, we will have a contingency force to prevent this,'' Castro said.
FIFA's director of security Ralf Mutschke called the security lapse before Wednesday's 2-0 victory by Chile over Spain ''embarrassing.'' Four days earlier, at least 10 Argentine fans were detained after jumping fences at the famous stadium to see their team play Bosnia-Herzegovina.
''This is a challenge for us,'' said Roberto Alzir, a top Rio state security official in charge of policing the World Cup. ''This is a very complex operation. ...We had specific failures, but various other invasion attempts were avoided by public and private security forces.''
He did not say what they were.
He said the Maracana was difficult to police because of its location in the heart of the city, and because it attracts tourists.
''We have to understand that Maracana is a tourist attraction and so we cannot prevent people from getting close to the Maracana unless the situation becomes abnormal,'' Alzir said.
Alzir said people without tickets were free to mill around outside the stadium and soak up the atmosphere, which is not allowed at some other World Cup venues.
He left open the possibility that Brazil's armed forces could be used.
''If the situation reaches the point where the measures being taken are not enough, we will have to think about different measures to take,'' Alzir said. ''The armed forces are our partners. They are available if we need them. The president (Brazil President Dilma Rousseff) has made a few men available to work with us.''
The number of private security workers at Sunday's match could also be increased from the 1,037 at the last game. Hilario Medeiros, security manager for Brazilian organizers, said up to 1,300 were available but did not say how many would be deployed on Sunday.
The private security forces work inside the stadium.
Sunday's is the third of seven matches there. It is the venue for the final on July 13.
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