Spanish police on Monday said they had arrested three "extremely dangerous" suspected mafia members wanted in Italy for crimes including attempted murder, weapons trafficking and money laundering.
A police statement said the suspects were "one of the heads of a dangerous family clan" of the Neapolitan Camorra, his son, and his son-in-law, without naming the three.
They were recently detained in the southern Spanish coastal town of Marbella, where many international criminal gang members have settled in recent years.
The investigation began when Spanish police found out that the clan's boss, who is wanted for money laundering, had fled to Spain from Italy.
He was tracked down to a house in Marbella rigged with "extensive security features" which he nearly never left, according to the statement.
Police first arrested the son, who faces a 30-year prison sentence and is accused of attempted murder and weapons trafficking, when he left the house to go into the city centre.
Then on Sunday police captured the crime boss and his son-in-law as they were leaving the fortified home, the statement added.
The latter faces a 20-year sentence on accusations of drug trafficking and tobacco smuggling.
The operation was carried out with the help of the Italian police.