- Scarlett Keeling, British teen, sexually assaulted and killed in Goa
- Relatives of 10 foreigners allegedly killed in Goa write to PM
- They demand an "unbiased and independent" probe
Minna Pirhonen -- the mother of Finnish national Felix Dahl, who was found dead in the tourist state in January 2015 -- said on Wednesday that the families had couriered a letter to the PM's office last week.
Goa Police and tourism officials were not immediately available for comment on the letter to the Prime Minister.
"The quality of the work of the police in Goa should be investigated. Instead of investigating the murders and killings, the local police want to cover up the truth," read the letter, according to news agency AFP.
The open letter, dated May 21, claims the investigation "is needed to reveal the connections between the locals, the police in Goa, drug mafia and politicians and their involvement in the deaths of tourists and locals in Goa".
The deaths of several foreigners in Goa over the last decade or so, many in suspicious circumstances or from drug or alcohol abuse, have blighted the coastal state's reputation as a major tourist haven.
The most high profile was that of 15-year-old Scarlett Keeling, whose bruised and semi-naked body was found in shallow water on a beach in 2008. Her case made international headlines and cast a spotlight on the seedy side of Goa.
Police initially dismissed her death as an accidental drowning but opened a murder investigation after Keeling's mother, Fiona MacKeown, pushed for a second autopsy.
Further examination proved her daughter had drugs in her system and had been sexually assaulted, and revealed Ms Keeling had suffered more than 50 injuries.
Pirhonen, whose 22-year-old son Felix was found with skull wounds and whose death was attributed to an accidental fall by local police, signed the letter on behalf of relatives of nine other victims, including Keeling.
In March, the body of 28-year-old Danielle McLaughlin, a dual British-Irish citizen, was discovered naked in a field. Police have charged a 23-year-old named Vikat Bhagat with her rape and murder.
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