Police also recovered valuables worth more than a €1 million ($1.1 million) stolen by the group from a jewellery shop on the island of Fuerteventura, part of Spain's Canary Islands, as part of the operation, they said in a statement.
The authorities declined to give further information, saying full details would be provided at a press conference on Thursday in Las Palmas, the capital of the archipelago off the Moroccan coast.
Members of the "Pink Panthers", a loosely-aligned network of criminals, are drawn from paramilitary circles in the former Yugoslavia.
The group, who have a weakness for expensive watches, have staged more than 380 robberies on luxury stores in Europe, the Middle East, Asia and the United States since 1999, making off with booty worth more than €330 million ($362 million), according to Interpol.
Known for their spectacular heists, the gang drove two cars into a Dubai shopping mall and through the window of a jewelry store in 2007, swiping goods worth €11 million in a raid lasting less than a minute.
The following year the group walked away with loot worth up to €85 million after entering the Harry Winston jewellers in central Paris disguised as women.
Once seemingly untouchable, the gang has faced setbacks over recent years, with members arrested in a number of other countries including France, Greece, Italy and Japan, as well as Switzerland.
The gang was given its name after British detectives found a diamond ring hidden in a jar of face cream, echoing an incident in Peter Sellers' 1963 comedy "The Pink Panther".