Three men broke into an art gallery in the affluent center of Madrid, near the Museo del Prado, and walked away with 50 paintings worth an estimated €400,000.

The thieves entered the Puerta de Alcalá gallery in the early morning hours of Thursday, December 4. They first broke into the adjacent premises, a former bar that has been closed for over a year, and then punched a hole through the wall that led to the gallery. They managed to deactivate the gallery’s alarm system and proceeded to take the artworks.

According to reports, the heist was anything but subtle. The thieves spent almost three hours moving the paintings from the gallery to a van parked in the street.

In fact, a security guard from a construction site nearby spotted the men and asked them what they were up to. The men replied that they worked for the gallery and were transporting the large group of artworks to an exhibition. Satisfied with the answer, the security guard walked away.

A week later, there are still no leads as to the whereabouts of the paintings. “We think they might have been taken outside of Spain,” Lola Moreno, from Puerta de Alcalá gallery, told artnet News. “The security guard said two of the three men had Eastern European accents, so the paintings might have been trafficked. The thieves also took our invoice books, so we fear they might try to pass any sales as legit,” she continued. Initial reports claimed that 70 paintings were stolen. However, the gallery has subsequently lowered that figure to 50.

The gallery specializes in 20th century realist and impressionist painters from Spain. Among the stolen works are 14 paintings by the Sevillian artist Pablo Segarra Chías, which were meant to be shown as part of a solo exhibition. The exhibition opened last night despite the theft. Works by the Valencian painter Eustaquio Segrelles and Juan González Alacreu were also taken by the thieves.

“This has destroyed us,” Pedro Márquez, who owned the gallery for decades before passing the baton to his son, told the Guardian. “It’s left us in a really tough situation. Forty years of work and they just walked out with it.”