Paraguayan prosecutors said Friday that they will seek pre-trial detention for six men arrested this week on suspicion they were working for Mexico's powerful Sinaloa drug cartel.

The four Mexicans and two Paraguayans were nabbed on Wednesday in an operation that led to the seizure of 308 kilos (678 pounds) of cocaine from a home in the Asuncion suburb of Villa Elisa

The drug consignment was destined for the Netherlands, according to Paraguay's Senad counternarcotics agency.

All of the suspects declined to answer questions during Friday's session at the Attorney General's Office, prosecutor Zulli Figueredo told EFE.

The men were taken back to holding cells at Senad headquarters pending their arraignment before a judge, Figueredo said.

Jimmy Waine Gallien, a Mexican national identified as the leader of the group arrested in Villa Elisa, was staying at a luxury hotel in Asuncion prior to the bust.

Investigators had the six men under surveillance for the past three months as part of a joint operation with Brazilian intelligence, Senad said.

Drug traffickers have installed clandestine labs in Paraguay to process Bolivian coca into cocaine for subsequent sale in Brazil, Argentina and other countries, authorities say.

The Sinaloa cartel was founded by the notorious Joaquin "el Chapo" Guzman, currently in a Mexican prison awaiting his possible extradition to the United States.