Watch more in iWantv or TFC.tv

MANILA (UPDATE) - Pharmally executive Linconn Ong had divulged "very vital" information about former presidential economic adviser Michael Yang supposedly financing the firm in its deals with government, Senator Panfilo Lacson said Tuesday.

Lacson said he and Senate President Vicente Sotto earlier talked to Ong during which he "indicated that he wanted to say something in an executive session."

"There was already information shared by Ong as well as the other guy from Singapore that Michael Yang indeed loaned money to Pharmally to purchase medicines from TigerPhil and even other medical suppliers," Lacson told ANC's Headstart.

"Even without the corroborative statement from Linconn Ong, I think we have sufficient (evidence) to conclude or even suspect that Michael Yang had something to do with the procurement of medical supplies by PS-DBM (Department of Budget and Management's procurement service)."

The Senate Blue Ribbon Committee last week arrested Ong for allegedly evasive answers and failing to submit several financial documents it subpoenaed.

He was set to be transferred to Pasay City Jail but requested to speak before the committee in an executive session, which his lawyer denied.

• Pharmally's Linconn Ong won't speak in Senate executive session, says new lawyer

The Senate can hold Ong under its custody until it adjourns sine die or until the committee report has been approved, Lacson said.

"If he continues to be evasive, if he continues not to cooperate, then I would guess he will stay until new Year’s Eve in the Senate premises. It’s all up to him," he said.

President Rodrigo Duterte earlier threatened he would "extract" officials detained by the Senate in connection with its investigation into corruption in government.

• Duterte: I will extract officials detained by Senate in corruption probes

The chamber has yet to establish a connection between Pharmally, DBM, and Malacañang but Duterte continues to attack the senators and the legislative inquiry, Lacson said.

"No there’s no connection that has been established so far. Not the Palace, not the President, not even Senator Bong Go. Bakit all in ang Presidente sa pagdedepensa? Malimit na ngayon yung kanyang Talk To The Nation and iisa lang ang kaniyang topic, hitting the Senate, defending Pharmally and defending everybody else," he said.

(Why does President go all in in defending them? His Talk To The Nation has become frequent and his only topic is hitting the Senate, defending Pharmally and defending everybody else.)

The House of Representatives' parallel investigation into the medical supply procurement aims to protect Malacañang, Lacson added.

"I still cannot understand bakit kailangan protektahan ang Malacañang eh wala pa naman naglilink sa Malacañang tungkol dito sa anomalous transactions ng Pharmally sa PS-DBM," he said.

(I still cannot understand why it has to protect Malacañang when no one has linked Palace to the anomalous transactions of Pharmally with PS-DBM.)