Security at the World Cup soccer tournament has been beefed up following an outbreak of violence among celebrating Mexican fans early this morning that reportedly left two persons dead and 100 arrested.

Mexico beat Belgium, 2-1, here Tuesday and the performance was followed by partying in the streets throughout the capital city. An estimated 100,000 people danced, sang, waved flags and chanted, "Mex-i-co, Mex-i-co." Not even a steady rain could dampen the celebrations.

But the good feelings did not last.

About 200 persons were injured and 50 were hospitalized after things got rowdy in the early morning, said a spokesman for the city police department, who asked not to be identified. Later, unconfirmed, reports said two persons had died as a result of the clashes.

Police went in force to the Monument to Independence, a center of the activity, about 2 a.m., where they found a crowd of about 2,000. Armed with clubs, they began dispersing the crowd.

With tickets for World Cup matches priced out of the range of many residents here, the city government has installed giant outdoor television screens in three parks in outlying districts.

The TV screens -- 40 feet by 15 feet -- are accompanied by game booths and children's rides, and food is sold by vendors. The quality of the telecasts is mediocre, at best, but with the carnival-like atmosphere, many families have come to the parks only mildly interested in the matches.

The city government, in a news release, said the screens were installed in consideration of the poorer fans and to discourage others from trying to force their way into the stadiums for sold-out matches.

Stadium ticket prices for the World Cup range from 2,210 pesos (about $4) to 26,500 ($50). Many laborers earn about $4 a day.

Televisa, Mexico's TV and entertainment conglomerate, and Imevision, the state TV network, are combining to provide all the pictures and sounds from the World Cup going out world-wide. And because of a sound failure during the Brazil-Spain game Sunday, broadcasters world-wide are up in arms.

John Bromley, who heads England's International Television Sports commercial system, said his company may withhold payments to the Mexicans because of the sound failure. The European Broadcasting Union protested because 20 nations were without sound for much of the match.

Bromley said the foulup ranked as "one of the biggest broadcasting disasters in sports history."

Today, Mexican television lost the picture from the West Germany-Uruguay match in Queretaro four times in the second half, totaling five minutes.