PODGORICA, Montenegro – Montenegro’s government on Tuesday rejected criticism from international watchdog groups over the months-long detention of an investigative journalist on charges of drug-trafficking.

The government said that the indictment and detention of Jovo Martinovic have nothing to do with his professional work and were the result of a criminal investigation.

Martinovic has probed crime and corruption for various international media outlets.

He was arrested in October last year on suspicion of “criminal association and illegal production, possession and distribution of narcotics.”

He was charged six months later with being a member of a drug-trafficking ring. Martinovic has denied the charges insisting that all the contacts with criminal groups were in the context of his professional work.

Three human- and media-rights groups have demanded in a letter to Montenegro’s prime minister, Milo Djukanovic, that the authorities release Martinovic, expressing concern that his detention was motivated by his investigative journalism.

The Committee to Protect Journalists, Human Rights Watch and Reporters Without Borders said Monday Martinovic’s detention and prosecution “violate his rights to liberty and due process and disregard Montenegro’s obligations to respect press freedom.”

Srdjan Kusovac, an adviser to Djukanovic, insisted in a statement that Martinovic’s detention was in line with the law and that he will have a fair trial.

Montenegro has been invited to join NATO and is seeking European Union membership.