DALLAS – A former Dallas police officer has been charged with a series of rapes and homicides after his DNA was linked to a number of cases, including two of the most notorious slayings in the city’s history.

Michael David Yates, 34, was arrested last month on the same day that Dallas police issued warrants for his arrest in connection with the rape and murder of 7-year-old Nicole Smallwood and 44-year-old Patricia Sarinana.

The girl was raped and killed by a knife in her South Dallas neighborhood in 2009. Sarinana was killed by a gunshot in early June 2012 in East Dallas.

DNA evidence collected at Sarinana’s murder scene had not yet been linked to Yates, the Dallas Morning News reported, but a review of the missing-person report listed him as a “person of interest.”

Sarinana’s mother said at a news conference that the family had hoped for justice through the many years that they waited for the results. “No one should have to go through a sleepless night wondering if that person is coming to do them harm,” she said.

More DNA samples were taken from Yates after his arrest in connection with Sarinana’s death, according to the Morning News. It was the same forensic science that police used on him to link him to the child rape and killing a year earlier.

Yates made his first court appearance Tuesday, where a judge ordered that he be held without bond, the Morning News reported. He faces charges of murder, aggravated sexual assault of a child and indecency with a child.

Dallas police said that Yates has also been connected to the unsolved 2008 rape and slaying of a 13-year-old girl and a 20-year-old woman who was strangled and sexually assaulted in 2011.

Police said that they have a blood sample from Yates, who served as a Dallas police officer for two years, but that it is not the same sample that they have tested and linked to the other cases.

Dallas police officials said that Yates became aware of being a DNA suspect in 2014. Investigators took his DNA samples at that time after he had left the force.

Yates was taken into custody in September and has been jailed in Dallas County since then, according to the Morning News.