Operatives of the Bureau of Jail Management and Penology (BJMP) held a surprise inspection at Marikina City Jail on Friday.
The operation called "Oplan Greyhound" failed to yield any contraband like illegal drugs and firearms.
Marikina City Jail warden Chief Inspector Jojie Pangan is relieved with the result.
Operatives only saw electric fans, ballpens and clothes of inmates.
The problem seen at the detention facility is overcrowding.
Marikina City Jail is built only to house 96 detainees.
Right now, 981 persons are languishing inside the city jail.