Washington, Dec 10 : A former Minneapolis police officer who knelt on George Floyd's back has been sentenced to three-and-a-half years in prison for his role in the latter's murder in 2020. On Friday, a Hennepin County Court judge sentenced J. Alexander Kueng to 42 months -- 3.5 years -- in prison for aiding and abetting manslaughter for a state charge, reports Xinhua news agency. This sentence will run concurrently with Kueng's federal sentence. He is serving three years in federal prison for violating Floyd's civil rights. Floyd, a 46-year-old African-American man, died on May 25, 2020, after an encounter with the Minneapolis police, during which officer Derek Chauvin knelt on his neck for more than nine minutes. Kueng and two other responding officers, Thomas Lane and Tou Thao, were also present and on duty. Video footage of the arrest shows Kueng and Lane assisting Chauvin by helping to hold Floyd down. Thao, meanwhile, kept concerned bystanders away. Chauvin was sentenced in a federal court to 21 years in prison earlier this summer for violating Floyd's civil rights. The sentence is running concurrently with Chauvin's state sentence of 22.5 years after he was convicted for second and third-degree murder, as well as second-degree manslaughter. In February, Kueng, Lane and Thao were also found guilty on federal civil rights charges. The officers were charged with showing "deliberate indifference to (Floyd's) serious medical needs" during the attempted arrest. Floyd's death sparked outrage and protests across the US in the summer of 2020 against police brutality and systemic racism. /IANS