MANILA - Justice Secretary Vitaliano Aguirre on Tuesday said the lower House investigation confirmed allegations of widespread corruption and a thriving drug trade inside the National Bilibid Prison (NBP) during the term of Senator Leila de Lima as secretary of justice.

In a press conference following the hearing conducted by the House of Representative's Justice Committee, Aguirre said that aside from the testimony of the witnesses, the number allegedly used by de Lima in communicating with convicted drug lord Herbert Colangco in 2014 was among the most incriminating evidence presented in the investigation.

Aguirre said they are coordinating with PLDT for the records of the said mobile number.

Meanwhile, Aguirre denied allegations made by de Lima that the Justice Department harassed and coerced the inmates to testify against de Lima. Aguirre claimed that the witnesses' demeanor confirmed their willingness to testify against the former justice chief.

Aguirre vouched for the credibility of the witnesses he presented and questioned during the hearing, saying their convictions do not negate their credibility, unless these involve lying or stealing.

The justice chief distanced President Rodrigo Duterte from the Congressional probe, as opposed to de Lima's allegations that the president is behind the investigation. He said he has not talked to the president yet regarding the probe.

Aguirre said de Lima and his alleged cohorts will be indicted once the Department of Justice (DOJ) formally files cases against them.

Aguirre also claimed that someone with a higher position than de Lima benefited from the alleged corruption inside the national penitentiary.

He said his team is working on revealing details of this person's bank accounts in the next hearing. - with a report from Miguel Dumaual, ABS-CBN News