Thieves entered a Belgian church on Friday and stole a work of art that the pastor believed was made by Renaissance great Michelangelo. Though the wood panel painting has been in the parish for years, its potential Old Master status was only recently identified, making it likely that the thieves suspected it was indeed an authentic Michelangelo.

Former Belgian senator Etienne Cooreman, a parishioner of Sint-Ludgerus in Zele—a town 45 miles north of Brussels—donated the work to the church 16 years ago. Jan van Raemdonck, the church’s pastor, noticed that a known sketch by Michelangelo features the exact same composition of the Holy Family as the painting.

The circa 1538 chalk drawing by Michelangelo shows a sleeping baby Jesus draped across Mary’s lap as Joseph and John the Baptist watch over him. It is from the Portland Collection, amassed over centuries by the UK’s aristocratic Cavendish-Bentinck family. The collection opened a public gallery three years ago, putting the rarely exhibited piece, titled Madonna del Silenzio, on display.

Van Raemdonck shared his theory with just a few people and had made arrangements to have Michelangelo expert Maria Forcellino examine the painting.

Michelangelo, Madonna del Silenzio (circa 1538). Photo courtesy of Mark Asher/The Harley Gallery.

“I didn’t talk about my suspicion about the painting in the church,” Van Raemdonck told the Guardian. “I wanted to wait for the experts and if they said it was a Michelangelo I would have improved the security of the building. I only told some family, friends, and the church’s council. I told about 20 people, and never in public.”

The painting was discovered missing on Friday morning, when two women arranging flowers noticed that the 220-pound work was not hanging in its customary spot above the altar. Nothing else was taken from the church.

Jan Van Raemdonck with the painting he suspected was a Michelangelo. Photo by Jan Van Raemdonck via Facebook.

A witness is said to have seen a young man outside the church early Friday morning wearing dark clothes and a hoodie. The church did not have alarms, and a side door was found open in the morning.

Should the work truly be by Michelangelo, Van Raemdonck estimates it could be worth as much as $144.8 million, according to TIME. It would be the only work by the artist in Belgium. As of press time, Van Raemdonck had not responded to artnet News’s request for comment.

Another version of the same composition resides in the collection of London’s National Gallery, where it is attributed to Marcello Venusti after Michelangelo. There are at least two other known Venusti copies, in the collections of the Alte Pinakothek in Munich, and the Kunsthistorisches Museum in Vienna.