Former president Corazon Aquino said the man who killed her husband, Ninoy Aquino, 19 years ago, is still powerful, adding that the search for the mastermind should continue.

In 1989, the Supreme Court ordered the imprisonment of 15 soldiers and a general who were indicted by an anti-graft court for the murder.

During a speech at the commemoration of the 19th death anniversary of the slain senator, the former president said: "Some of those behind the killing are holding positions in government." She did not give more details.

Her son, Congressman Benigno "Noynoy" Aquino III, asked those who know the real story behind his father's murder on August 21, 1983, to come out in the open and state names.

The assassination of the former senator during a homecoming at Manila international airport (after three years of living in exile in the U.S.) was blamed earlier on ex-dictator Ferdinand Marcos.

But sources said Marcos was then undergoing a kidney transplant operation at the presidential palace.

A fact-finding court said those who killed the former senator were one of the three escorts who brought him down the service stairway of the China Airlines plane.

Their plan was to bring Aquino down to the tarmac where a car was waiting to bring him to a military headquarters.

But he was shot at the service stairway, the court found out, and not on the tarmac where a fall guy, Rolando Galman, an alleged communist who sneaked into the heavily-guarded tarmac, was also shot because he had gunned down Aquino.

Brig. Gen. Luther Custodio, head of the defunct Aviation Security Command (AVSECOM), was convicted and imprisoned for the murder. He was the key to the identity of the murder's mastermind, but he died of liver cancer immediately after his conviction.

Many said they would speak more on the murder, but sources said they would just repeat the old government version that Galman was responsible for the murder.

Aquino was Marcos's political rival because the former was a vocal critic of the martial law rule.