The Philippines is seeking to retrieve three major paintings that an aide to Imelda Marcos, the wife of the country's notorious dictator, has gone to jail in the U.S. for attempting to sell.

Vilma Bautista, 75, was sentenced last week to six years in a New York prison for trying to sell artwork that once belonged to Imelda Marcos, for whom she once worked as a secretary. She was convicted in November of conspiracy and tax fraud in relation to top-tier paintings owned by Marcos.

In 2010, Bautista illegally sold Marcos's major Claude Monet from his water-lilies series, “Le Bassin aux Nymphéas,” for $32 million to a London gallery. The work is also called “Japanese Footbridge Over the Water-Lily Pond at Giverny” (1899).

She did not disclose the sale on her state tax returns which led to an investigation by the state Department of Taxation and Finance.

There are three other works that officials want to recover because they say they belong to the Filipino people, including Monet's “L’Église et la Seine à Vétheuil,” Alfred Sisley’s “Langland Bay” and Albert Marquet’s “Le Cyprès de Djenan Sidi Said.”

The Filipino government will file a civil case in New York to recover the paintings.

The three artworks are among 150 paintings and other ill-gotten wealth amounting to $10 billion that have been sought by the Philippines since Ferdinand Marcos was ousted in 1986.

Known the world-over for her outrageous shoe collection amassed during the couple's 20-year rule, Imelda Marcos is now a congresswoman in the Philippines. Her husband died in Hawaii three years after his ousting.