The Committee to Protect Journalists (CPJ) on Friday demanded Sri Lankan authorities to charge or release a freelance Tamil journalist, Parameswaree Maunasami, detained for nearly a week.
Maunasami, a journalist with the Sinhala-language weekly Mawbima, was arrested at her home south of Colombo on November 24, along with another Tamil woman, according to news reports.
"We had called the authorities to clarify why they have detained Parameswaree Maunasami," said CPJ Executive Director Joel Simon in a statement released on Thursday.
"Tamil journalists have too often been harassed because of their political affiliation, their ethnicity, or their reporting. Such actions harm the ability of all Sri Lankan journalists to cover this period of escalating violence."
CPJ is a New York-based, independent, non-profit organisation that works to protect press freedom worldwide.
Maunasami is being held under anti-terrorist legislation that allows for prolonged detention without charge. The authorities gave no reason for her arrest.
Mawbima has distinguished itself among Sinhala-language newspapers for an editorial line that is critical of both the Sri Lankan military and the Liberation Tigers of Tamil Eelam (LTTE) rebels, the reports said.
Colleagues of Maunasami said they believed she might have been arrested for her work at the weekly newspaper covering the Tamil separatist movement.
Fighting between the government and rebel forces has escalated in the recent months, and on Monday LTTE leader Velupillai Prabhakaran called the 2002 ceasefire 'defunct.