Members bore banners and chanted slogans such as “Impeach mga corrupt!”, underscoring their call for stronger action against graft in government.
In speeches during the brief program, ATOM leaders reiterated concerns over perceived impunity, saying corruption remains pervasive and urging decision-makers to act with urgency.
The group specifically called for the continuation of impeachment proceedings against Vice President Sara Duterte, citing allegations of wrongdoing that have drawn public scrutiny.
The march proceeded without reported incidents, and officials did not immediately report any arrests or violence.
Organizers described the activity as part of sustained civic pressure to hold public officials accountable, without specifying the size of the crowd.
The demonstration comes amid developments in Congress involving impeachment complaints against high-ranking officials.
On Saturday, Rep. Terry Ridon said a House justice panel had secured votes supporting a finding of probable cause to impeach Vice President Duterte and predicted that the full House could reach the one-third threshold required to transmit articles of impeachment to the Senate.
Separately, the House Committee on Justice voted unanimously on 29 April to find probable cause to impeach Duterte in two consolidated complaints.
Sunday’s march is the latest activity by ATOM, which previously organized commemorative walks and motorcades marking historic events and continuing its anti-corruption advocacy.