Two US police officers have been fired after a photo emerged showing them re-enacting a chokehold used on a black man before he died at a memorial site to his death, Colorado police said in a statement.

Elijah McClain, 23, died last August in Aurora three days after police put him into a chokehold, was injected with ketamine to sedate him and suffered a cardiac arrest. Police this week ordered a special investigation into his death which came under the spotlight after the killing of George Floyd by police in May sparked nationwide anger and protests.

Officers Erica Marrero, Kyle Dittrich, and Jaron Jones imitated the chokehold used to subdue McClain in October last year. In a statement posted online, interim Aurora police chief Vanessa Wilson confirmed on Friday that Marrero and Dittrich had been fired.

The third officer pictured, Jones, resigned on Tuesday, she said. She added she understood "the devastating impact this incident has had on the relationship between the community and the Department."

A fourth officer, Jason Rosenblatt, was also fired on Friday, she said. He had been sent the photo by one of the trio and had responded "haha", local US media reported.