The rally was marred by scuffles between the demonstrators and the officers. People are angry over the mismanagement of thousands of flood-control projects in the country that cost more than $9.5 billion. In July, President Ferdinand Marcos Jr. established an independent commission to investigate what he called "anomalies" during their construction. The protesters at Manila's Luneta Park waved national flags and chanted "Jail them!" READ MORE: Shooting suspect in US shouted 'Free Palestine' - witnessSeveral officers were wounded during the scuffles and required hospitalization, according to Manila's mayor.