The number of Iglesia ni Cristo (INC) members gathered at the People Power Monument in Quezon City dropped to around 4,000 as of early Wednesday morning, police said.
The crowd was part of the INC-led protest against corruption in government, which began Tuesday at the EDSA landmark.
According to the Quezon City Police District, the crowd peaked at about 15,500 at around 7 p.m. Tuesday before gradually thinning out through the night.
Police said the number went down to 12,000 by 9:30 p.m., 8,000 by 10 p.m., and 5,000 by 11 p.m.
As of 5 a.m. Wednesday, the QCPD estimated the remaining crowd at around 4,000.