Police reform and civil-rights activists joined thousands of people on Sunday to mark the fifth anniversary of George Floyd's murder and decry U.S. President Donald Trump's administration for setting their efforts back.

The Rev. Al Sharpton said at a graveside service with Floyd's family in Houston that Floyd, 46, represented all of those "who are defenceless against people who thought they could put their knee on our neck."

He compared Floyd's killing to that of Emmett Till, a 14-year-old Black child who was abducted, mutilated and slain in Mississippi in 1955 after being accused of offending a white woman.

"What Emmett Till was in his time, George Floyd has been for this time in history," Sharpton said.

Events in Minneapolis centred around George Floyd Square, the intersection where police officer Derek Chauvin used his knee to pin Floyd's neck to the pavement for 9½ minutes, even as Floyd cried "I can't breathe."

By midday Sunday, a steady stream of people were paying their respects at a memorial in front of Unity Foods (formerly know as Cup Foods), where Floyd was killed. Across the street, activists had set up a feeding area at an old gas station that has often served as a staging area since Floyd's death. In the middle of the street, a fake pig's head was mounted on a stick. The head wore a police cap.

Events started Friday with concerts, a street festival and a "self-care fair," and were culminating with a worship service, gospel concert and a candlelit vigil on Sunday.

Even with Minneapolis officials' promises to remake the police department, some activists contend the progress has come at a glacial pace.

"We understand that change takes time," Michelle Gross, president of Communities United Against Police Brutality, said in a statement last week. "However, the progress being claimed by the city is not being felt in the streets."

Slow pace of change

Activists had hoped that the worldwide protests that followed Floyd's murder on May 25, 2020, would lead to national police reform and focus on racial justice.

Under president Joe Biden, the U.S. Justice Department had aggressively pushed for oversight of local police it had accused of widespread abuses. But the Trump administration moved Wednesday to cancel settlements with Minneapolis and Louisville that called for an overhaul of their police departments following Floyd's murder and the killing of Breonna Taylor.

Trump also has declared an end to diversity, equity and inclusion initiatives within the federal government, and his administration is using federal funds as leverage to force local governments, universities and public school districts to do the same. Republican-led states have accelerated their efforts to stamp out DEI initiatives.

In Houston, Sharpton castigated the administration's settlement cancellations, saying they were "tantamount to the Department of Justice and the president spitting on the grave of George Floyd."

"To wait to the anniversary and announce this, knowing this family was going to be brought back to the brokenheartedness of what happened shows the disregard and insensitivity of this administration," he said. "But the reason that we will not be deterred is that Trump was president when George Floyd happened and he didn't do anything then. We made things happen. And we're going to make them happen again."

Detrius Smith of Dallas, who was visiting the Floyd memorial site with her three daughters and five grandchildren, told one granddaughter about how people globally united to decry racial injustice after Floyd's murder.

"It just really feels good, just really to see everybody out here celebrating the life, and the memories of George Floyd and just really remembering what happened," Smith said. "We want to do everything we can to work together so everybody can have the same equal rights and everybody can move forward and not have something like that to continue to happen in this nation."