CRITICS of human rights violations across the Commonwealth have piled further pressure on competing nations as Glasgow 2014 gets under way.

Amnesty International, trade unions and sexual equality campaigners have used the platform of the Games to raise the issue of abuses across many of the 53 Commonwealth nations, including the re-introduction of the death penalty, and the role of the Scottish police in training officers in regimes with poor human rights records.

Activists gathered at the Scottish Trades Union Congress in Glasgow last night for the launch of a report into abuses by Sri Lanka against its Tamil population.

The report alleges three decades of UK support for the majority Sinhalese-dominated military and police, using previously unseen British government documents and comes on the back of a UN war crimes investigation into the Sri Lankan conflict.

More than 3500 Sri Lankan police officers, including some senior commanders, have received training from the Scottish Police College (SPC) since 2007 through projects funded by the UK and Scottish governments.

Most of the training involves Scottish officers ­travelling to the island, but in some cases Sri Lankan police are brought to Scotland.

Shadow Foreign Secretary Douglas Alexander previously raised fears the Games risked being overshadowed by a human rights row if Sri Lanka's president Mahinda Rajapaksa had become chairman of the Commonwealth.

Author Phil Millersaid said as well as coinciding with the Games, the report has been launched "to offer a space to explore whether an independent Scotland could adopt a more sympathetic stance towards the Tamil independence movement", adding the role of Scottish Police College would "embolden the perpetrators" of human rights abuses.

Amnesty International, meanwhile, raised what it described as "a reprehensible U-turn on the death penalty" by Singapore following the double execution on Friday of two prisoners.

Siobhan Reardon, Amnesty International Scotland programme director, said: "It is extremely disappointing that, as we welcome Team Singapore to Glasgow 2014, one of the positive human rights stories we have shared is now no longer true."

The STUC has organised a campaign encouraging the Scottish Government and local authorities across the country to fly the rainbow flag in solidarity with LGBT people across the Commonwealth during the Games.

The flag will be flown outside St Andrew's House with the Commonwealth flag and the Saltire, the first time it has officially flown on a Scottish Government building.

Of the 53 Commonwealth states, 42 have laws that criminalise LGBT people, including life prison sentences.

Hundreds of refugees and asylum seekers fled to Scotland and the rest of the UK from countries such as Nigeria and Uganda due to persecution over their sexuality and gender identity.

It comes as leading gay rights campaigner Peter Tatchell called on First Minister Alex Salmond to "express his grave concern at the persecution of lesbian, gay, bisexual, transgender and inter-sex people in 42 of the 53 Commonwealth member states".

Mr Tatchell added: "We urge him to appeal to all participating countries to adhere to Article 7 of the Commonwealth Games Federation constitution, which prohibits all discrimination,"

Bisi Alimi, LGBT activist from Nigeria, said; "As athletes converge in Glasgow, it is important to align with LGBT people of the Commonwealth."