Amnesty International says there is still a climate of fear and intimidation in Sri Lanka, partly because citizens continue to disappear in what are known as 'white van abductions.'
This year's Commonwealth Heads of Government Meeting was dominated by debate around Sri Lanka's human-rights record.
Prime Minister John Key says while that is undoubtedly an issue, he believes Sri Lanka is making progress towards becoming a free and peaceful society.
But Steve Crawshaw of Amnesty said it is incomprehensible how world leaders can ignore ongoing abuses, including the abduction of thousands of citizens - in some cases straight off the street.
Mr Key says Sri Lanka's President Mahinda Rajapaksa told him there is process in place to register everyone who is missing.
A Sri Lankan woman holds pictures of her missing son. Photo: RNZ
In Colombo, Radio New Zealand's Parliamentary chief reporter met five women who have lost loved ones in abductions.
One said two of her sons, aged 34 and 30, were taken in 2010, and she had not seen them since.
Her sons ran a business and she believes the motive for their abduction was financial.
A Tamil woman broke down as she talked about her son who was working in his cafe when he was taken.
Another Muslim woman said her son, aged 25, was driving a Tamil passenger in his tuk-tuk. He was also taken when he tried to help during the abduction of that passenger.
The women said they understood they were putting themselves in danger for speaking out, but drawing attention to the plight of their sons is more important.
They said they hold onto the hope their sons are still alive, but need international pressure to be kept on the Sri Lankan government.
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