"Believing that you have gone was extremely difficult." Asylum seekers mark 1 year since the bashing death of their friend.

Asylum seekers at the Manus Island detention centre yesterday marked one year since Iranian man Reza Barati was beaten to death while in custody.

Mr Barati was killed in a riot at the centre when locals overran the Australian-run detention centre in Papua New Guinea.

Security guards, police and others stormed the compound on the night of February 17, 2014, killing the 23-year-old Iranian with blows from timber, fists and a rock. Dozens of others were injured.

The ABC has obtained a letter from another Iranian asylum seeker still inside the centre which has paid tribute to Mr Barati’s friendship, and to the thousands of Australians who held protests and vigils after his death.

“We had not expected that muscular and strong Reza Barati was beaten to death in an unfair manner,” the letter said.

“You are not aware that thousands of kind Australians held a candlelight vigil in memory of you and remained on the streets for a few hours to prove that humanity is still alive.

“The Australian people are not similar to their racist government.”

Read more: Two men wanted over Manus Island death

Two Papua New Guinean men have been charged with murdering Mr Barati, but the case has not progressed in months.

Police on Manus Island could not be reached for comment.

“Your murderers and their bosses are freely walking around,” the letter said.

“Your memory remains in our minds and hearts.”

A ceremony for Mr Barati had been planned for inside the detention centre on Tuesday night.

The letter also mentioned Hamid Kehazaei, an Iranian asylum seekers who died from septicaemia after cutting his foot at the Manus Island centre.

Read more: Arrests over murder of Reza Barati

“Reza, I know that freedom for you and Hamid was just a dream, it was an unachievable dream which was not fulfilled here, but now you guys are entirely free. Rest in peace,” the letter said.

The activist group Getup said those taking part in the vigil on Tuesday would light candles at sunset to publicise that little had changed at the centre since Mr Barati’s death.

Australians took to social media with the hashtag #LightTheDark to mark the incident and share images of candles and speak out against mandatory detention.

Around 1,000 asylum seekers remain in detention on Manus Island.

In Sydney, a skywriter wrote the words “Shut down Manus” to mark the anniversary.

The skywriting was organised by three artists who used crowd funding to pay for it.

In the days following Mr Barati’s death, thousands of Australians staged candlelight vigils to protest against his death.

This post originally appeared on ABC and was republished here with full permission.