Yeah, that was in the morning news on TV. Still can't figure how exactly they have managed to make it?
The earth quake sensors are too close to the stadium, so noice and racket from the sports fanatics is mistaken for earth quake vibrations. Earth quake sensors are pretty delicate and sensitive equipment, to say the least.
A real earthquake will register at several of the seismic stations in the network, so noise pollution affecting one station only is easy to spot and filter out.