Cooper was reported to be facing the sack earlier this week after a run of five successive Premier League defeats.
The 44-year-old was appointed within weeks of the takeover.
Local authorities reported that home fans were trying to get into the Juan Carmelo Zerillo Stadium, which was already at capacity and had no visiting supporters attending, with police using rubber bullets and tear gas to try and restore order. Play was suspended nine minutes into the match by the referee as tear gas from outside spread over on to the pitch. Both the Argentine Football Association and Primera Division condemned the scenes in La Plata, near Buenos Aires, which came days after a crush at an Indonesian football match resulted in the deaths of at least 131 people.