At least 58 people, including several children, were found locked inside a truck in Paris earlier in the week. The discovery came right after another group of migrants was saved from the back of another vehicle.
Emergency services were seen attending to the scene of the discovery, but there's been no public information available on the condition of the people found inside the vehicle.
The discovery took place in the early hours of August 26 during an inspection of the truck, which at the time was parked in a cul-de-sac in the centrally located 18th arrondissement of the French capital.
The driver of the vehicle, however, is yet to be found, and it is unclear at this point whether that person was aware of the presence of migrants in the back.
The Paris Public Prosecutor's Office said in a statement that a criminal investigation had been opened "on charges of aiding the illegal entry, movement, or stay of a foreign national in France as part of an organized crime ring."
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Irregular migrants taken into custody
The inquiry is being led by the Paris branch of the Office for the Fight Against Illegal Migrant Trafficking (OLTIM), the statement explained, adding that the agency would be tasked with determining whether "the truck was intended to transport them to a specific location as part of an organized network."
Police meanwhile told the AFP news agency that there was an undisclosed number of children among the group.
Some of the 58 migrants rescued from the vehicle were later found to be in France irregularly and were therefore placed in administrative detention, while others did produce legal papers.
In total, 32 people were found to have legal status and were released from custody.

Similar discovery just hours earlier
The discovery immediately follows another similar event the previous day, after a group of 19 migrants was discovered locked inside a refrigerated truck on a highway in Yvelines, located just to the southwest of Paris on August 25.
A local news outlet reported that the group included seven children. The same source also said that all passengers originally came either from Iran or Iraq.
This group, however, had reportedly boarded the vehicle without the driver's knowledge, hoping to travel as stowaways.
One of the occupants of that vehicle had reportedly notified emergency services about the crammed and potentially life-threatening conditions inside the truck.
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Clandestine journeys in refrigerated vehicles can be particularly dangerous given the frosty temperatures inside.
In addition to suffering hypothermia and losing consciousness, irregular journeys in trucks also carry a serious risk of suffocation due to a lack of ventilation.
In 2019, 39 Vietnamese migrants were found dead in a refrigerated truck outside London due to a combination of these circumstances.
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Clandestine journeys in France
These recent discoveries follow a broader trend in France, which appears to have undergone a slight uptick in the past 12 months.
Last November, four Iraqi men were arrested after being discovered inside a refrigerated truck in Rouen, Normandy.
Just a month prior, 11 Eritrean migrants were also found in a refrigerated truck in northern France.
Last summer, 15 refugees were found suffering from hypothermia at a rest stop in the northern town of Calais -- one of the departure spots for migrants hoping to reach the UK by irregular means.
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with AFP, dpa