Indian investigators have said they believe six policemen accused of planting drugs on an Israeli man in Goa were part of a larger racket framing foreigners in the popular holiday state.

The Central Bureau of Investigation (CBI) detained the six officers this week and charged them with conspiracy for allegedly planting drugs on Israeli David Driham, who was on a business visa in Goa in 2010.

"We are conducting an investigation as to why they were forced to do such (an) illegal act of planting drugs," CBI Deputy Inspector General Pravinkumar Salunke said late Thursday.

"There is a larger racket which we are exploring now. We need to investigate how they were planting drugs on people, especially foreigners."

Salunke said the accused police, who were part of an anti-narcotics cell, had fabricated the case against Driham, whom they claimed was a drug-dealer when he was held with a cocktail of drugs worth 381,000 rupees ($A7100).

The Israeli denied involvement in the narcotics trade and remains on bail.

The CBI began probing suspected links between Goa police and two alleged drug dealers, including Driham, in June last year.

In the other case, a Swedish model who dated alleged dealer Yaniv Benaim, also Israeli, secretly filmed him boasting that he was supplied with confiscated narcotics by members of the police.

Some 400,000 foreigners annually visit to Goa, a former Portuguese colony, where the availability of illegal drugs and aggressive dealing in and around its popular beaches has long caused concern to authorities.

The mother of a British teenager who was found dead on a north Goa beach in 2008 said that police were reluctant to investigate her daughter's death because of their links with local drugs gangs.