Combined operatives of the Bureau of Jail Management and Penology (BJMP) and the Manila Police District (MPD) conducted a surprise inspection of the Manila City Jail.
The prison is located along Oroquieta Street in Santa Cruz, Manila.
Under 'Oplan Greyhound,' authorities confiscated several bladed weapons from inmates.
The raid is ongoing as of noon on Monday.
BJMP personnel and cops from MPD – Station 3 based in Santa Cruz are particularly zeroing in on Building 13 and 14 of the prison complex for possible contrabands.
They are also inspecting prohibited items that may be hidden in the ceilings of the buildings.