According to the same source, the operation included 50 search warrants and before11am police had arrested five people in compliance with arrest warrants, one in flagrante delicto and another on suspicion of drug trafficking.

The arrests, as well as the seizure of "several" stolen items and tools used to extract them, were the result of 11 home and six non-domestic searches.

"Considerable amounts of fuel were also seized, suggesting that the suspects, in addition to this criminal activity, also engaged in fuel theft," added the PSP source.

Operation Carbono', which began yesterday morning, ran simultaneously in the districts of Santarem, Porto, Leiria and Coimbra, and targeted homes of suspected thieves, scrapyards and other places "referred to during investigations for illicitly selling these components, in the form of waste, from thefts of vehicles," the police said.

In a statement earlier this morning, the PSP said the operation stems from several investigations, under the guidance of the Public Prosecutor's Office of the respective districts and with the collaboration of the Portuguese Environment Agency.

"Since the beginning of 2020, when the first occurrences took place, PSP recorded about 2,600 thefts of catalytic converters throughout the national territory and an acceleration of this type of crime since the beginning of deconfinement," the statement added.