Tamil prisoners in Sri Lanka, some held without charge since the 1990s, have gone on hunger strike to press for their release.
Some 223 inmates have joined the fast in jails in Colombo, Anuradhapura, Jaffna and Kandy.
Most have been imprisoned on suspicion of links with the defeated Tamil Tiger rebel group.
Tamil politicians are calling on the authorities to either release them, grant them bail or put them on trial.
They are being held under the Prevention of Terrorism Act (PTA), which allows the security forces to detain people for up to 18 months without bringing them before a court.
But some have been jailed since 1997.
The UN’s human rights chief, Zeid Ra’ad al-Hussein, said in a landmark report last month that the government had acknowledged holding 258 men and women under the PTA but only 54 of them had been convicted of anything.
He said 60 had not been charged while 144 of the cases were still pending.
Human rights campaigners have in the past given a figure of more than 650 Tamil detainees and Mr Hussein said there was also an urgent need to investigate reports of secret and unacknowledged places of detention.
Fears of violence
“The government has pledged to the UN Human Rights Council that the PTA will be repealed,” a Tamil legislator, M A Sumanthiran, told BBC Sinhala.
“So they should release those detained under the PTA before repealing it.”
He said that since the government had rehabilitated and freed some 12,000 former Tiger fighters after defeating the rebels in 2009, there was no sense keeping the long-term detainees in jail.
Another Tamil politician, Northern Province Chief Minister C V Wigneswaran, wrote a letter to President Maithripala Sirisena saying there was concern that the hunger-striking prisoners might be dealt with violently by prison officers as, he said, had happened in the past.
He said inmates should be categorised, with some freed and others bailed – or charges swiftly filed and cases heard.
Nearly 30 prisoners of varied ethnicities died in prisons during rioting in 2012.
Mr Wigneswaran said a list of the Tamil prisoners could be prepared “within one week”.
But the UN’s Zeid Ra’ad al-Hussein said President Sirisena’s new government appeared to be “facing challenges” in drawing up such a list, which it says it is working on with Red Cross help.
The Sinhala-language media – which dominate national discourse – frequently refer to the Tamil prisoners as “terrorists”, while many of the Tamil population regard them as political prisoners.