French authorities are examining more than 150 DNA samples, fingerprints and traces found on tools and security equipment abandoned by the robbers after the the spectacular theft of priceless jewelry from the Museum of the Louvre in Paris.

Five days after the robbery that rocked France, Paris prosecutor Lore Bequiot said she retained “slight hope” that the jewels could be recovered and expressed “optimism” about the progress of the investigation, according to the Guardian. As he told the Ouest-France newspaper, “in the next 24 hours, we may have results that will give us directions, especially if the perpetrators have a criminal record.”

The gang arrived at the Louvre at 9.30 am on Sunday, shortly after the museum opened, using a stolen removal van with a 30-metre-high lift. Two of the perpetrators climbed to the first floor of the famous Apollo gallery, where the remaining jewels of the French crown are kept. Wearing fluorescent vests to look like workers, they smashed an unguarded window and used cutting wheels to open two display cases before fleeing in motorbikes driven by their accomplices.

In their attempt to burn the truck, the robbers failed and left helmets, wheels, cutting discs, a vest and other items at the scene, which are being analysed at forensic laboratories in Paris and the surrounding area. At the same time, authorities are examining frame-by-frame video from public and private cameras, and even from highways, in order to trace the escape route of the perpetrators.

More than 100 police officers, including members of the BRB Organized Crime Unit and art theft specialists, are involved in the investigation. Bequio said all possibilities are being considered, including the possibility of collusion from within the museum. She said the robbery bears “all the characteristics of an organized operation: careful preparation, boldness, specific targeting and an organized escape.”

The operation lasted less than seven minutes, while the two robbers who entered the room lasted just three minutes and 58 seconds. Although they dropped a crown adorned with diamonds and emeralds during their escape, they managed to snatch eight pieces of 19th century jewelry.

It was surprising that a similar robbery was described in a book in the children’s series “Fantomet”, published in the 1960s, which recounts the adventures of a 12-year-old superheroine.

Experts believe the jewelry is too recognizable to be marketed and will likely be dismantled. Becchio noted that “time is critical,” expressing hope that, with the global publicity surrounding the case, “the perpetrators will not dare to move far away and we can recover the jewelry if we act in time.”

According to Le Parisien, security footage shows that the robbers initially had difficulty opening the display cases and resorted to breaking small sections of glass to extract the jewelry. The alarm was triggered at 9.34 am, and two guards rushed to the scene but withdrew, possibly believing the robbers were armed.

The museum’s director, Laurence de Carr, admitted a “serious security failure”, pointing out before the French Senate that the museum’s outer walls were not adequately covered by cameras.