CHICAGO (CBS) — A Cook County Sheriff’s deputy died Sunday from complications due to COVID-19, the sheriff’s office announced.

Deputy Richard O’Brien was a 25-year veteran of the Sheriff’s office and was most recently assigned to the Civil Process division at the Skokie Courthouse, the Sheriff’s office said.

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He was known as a “highly-motivated and dedicated professional” who always asked to be assigned to the front line and always wanted to go the extra mile, the Sheriff’s office said.

O’Brien had continued to work after going through significant health issues, including a diagnosis of leukemia just this past January, the Sheriff’s office said.

O’Brien is survived by his wife, Cindi, and their three children.

A corrections officer with the Sheriff’s department also died last month from complications due to COVID-19, the Sheriff’s office said.

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Officer Sheila Rivera, 47, joined the Sheriff’s office in 2012 and most recently was assigned to the Residential Treatment Unit at the Cook County Jail, the Sheriff’s office said.

“The Sheriff’s Office considers her death to be in the line of duty and will be strongly advocating that her family receive all the benefits that designation affords,” the Sheriff’s office said. “In addition, Sheriff’s Office Peer Support staff have reached out to the family to offer any assistance we can give to help them during their time of grief.”

Another corrections officer, Antoine Stewart, was found dead at his home in Crestwood the same day, the Sheriff’s office said.

As of its last report on Stewart, the Sheriff’s office had been awaiting an autopsy to determine whether COVID-19 played a role in his death.

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Stewart joined the Sheriff’s Office in 2010.