A tug-of-war over a Russian citizen detained in Greece sheds light on a global struggle over policing the multi-billion-dollar cryptocurrency sector.

Authorities on Tuesday night ordered the detention of Greece’s former defense minister and his wife as he awaits trial over charges of taking kickbacks from arms procurement deals in the early 2000s and laundering the money, Reuters reported.

One of the masterminds behind the 2015 migrant smuggling network along the Western Balkan route and his accomplice were arrested in Athens, the Hellenic Police said on Monday.

A Greek court sent four leaders of an international migrant smuggling ring to jail for 1,400 years after police found and rescued 112 migrants from a cave and farm buildings in southern Crete a year ago, the UK National Crime Agency announced on Wednesday.

Maria Efimova, the former bank employee turned whistleblower in a corruption scandal involving the Maltese prime minister and the Panama Papers, turned herself over to police in Athens on Monday.

The Council of Europe has told Greece to improve anti-graft efforts in the legislative and judicial branches and to enhance transparency of party financing, according to two reports released Thursday.

The EU's migration chief has branded Greek prosecutors “perjurers” after he was named in a major corruption investigation into whether top politicians were paid bribes in exchange for fixing the price of various medicines.

On Wednesday, a Greek court showed support for Russia in a US-Russia legal tug-of-war over the alleged mastermind behind a $4 billion bitcoin money-laundering scheme, reported Reuters.

A Greek court gave the green light Wednesday for the extradition of Russian bitcoin fraud suspect Alexander Vinnik to the United States, Reuters reported.

Brazilian authorities expanded Friday their mammoth corruption investigation, Operation Car Wash, to include at least five Greek shipping companies, a US asphalt firm and a Brazilian ex-congressman.

Greece’s former transport Minister was found guilty on Friday of money laundering involving contracts between Siemens’ Greek unit and then state-controlled telecoms firm OTE, Reuters reported.

Seven Albanian drug trafficking suspects were arrested after authorities chased their speedboat for nearly 22 hours across the Mediterranean Sea in a movie-like operation involving high speed boats, helicopters and planes.

Greece’s chief corruption prosecutor, Eleni Raikou, resigned this weekend after being targeted by "unofficial power centers" over her investigation into alleged bribery of state officials by a Swiss pharmaceutical company.

EU authorities said  that Greek and Spanish police have arrested 17 people suspected of smuggling baby eels worth some €10 million (US$ 10.6 million) from the EU to China this year.

Turkish police busted a human trafficking ring Friday, detaining 23 alleged traffickers suspected of smuggling migrants from Turkey to Europe, local media reported.

Police in Athens said this week they have “managed to dismantle” a foreign crime ring alleged to be behind nearly 140 burglaries in the country since 2010.

Police have arrested a 33-year-old Greek man in connection with an organized crime ring, which they say has been scamming the elderly since 2012. 

Police action with the support of Europol saw 16 arrested in Greece and three in the Czech Republic as part of an operation against crime groups that allegedly made and distributed fake documents to illegal migrants looking to enter the EU.

Following a major crackdown on an international drug trafficking group in Greece on May 9, the Albanian opposition Democratic Party (DP) has accused the interior minister of protecting the alleged leader of the group, whom Greek media has dubbed the “Escobar of the Balkans.” “Escobar” is, according to the Balkan Investigative Reporting Network (BIRN), a former regional director of transport services who served as part of the Transport Ministry until last week.