ALBANY, N.Y. – At the outset of his murder trial Monday, prosecutors sought to label Edward Mero as a killer, motivated by sex and anger, who took the lives of two young women over a two-year period — then callously disposed of their bodies.

Mero, 29, is being tried for two counts of murder, and two more counts of tampering with physical evidence, for the homicides of Megan Cunningham and Shelby Countermine, both 23-year-old women. Opening statements led off the jury trial on Monday afternoon, with the first witnesses in the case following.

The timeline of Mero's alleged crimes began in January 2013, when his Arcadia Avenue home in Albany was destroyed in a massive fire. Mero's roommate, Megan Cunningham, was found dead in her upstairs bedroom after the fire, her body severely burned.

The fire was originally ruled as "accidental," but police took another look in 2015 after Mero became connected to a second death: the homicide of Shelby Countermine. The defense team painted Countermine as a drug-addled prostitute, but nevertheless her body was found dumped in a remote wooded area in the town of Coeymans in May 2015, after Mero was reportedly the last person to see her alive.

Eventually, Mero was charged with murder in both of the death investigations.

“Two young women, forever linked by a common killer," assistant district attorney Steve Sharp told the jury. "That killer ... is sitting just a few feet away from all of you [jurors].”

In a mostly circumstantial case, the prosecution will highlight the links between Mero and his alleged victims: not only did he live with Cunningham, but Mero also paid Countermine for sex. Their arrangement peaked in 2014, when prosecutors say Mero was paying Countermine $500 for hours-long sexual encounters.

On the day she disappeared, Mero was the last known person to see her alive. He says he kicked her out of his parents' house for shooting up heroin. Her body was found five months later, badly decomposed on Albany Water Department property. Mero worked for the water department at that time.

On Monday, Mero's attorney Cheryl Coleman seized on the prosecution's lack of hard evidence.

“No physical and no forensic evidence, and no DNA connects Ted Mero to the death of Shelby Countermine," Coleman said.

And on the fire that scorched Megan Cunningham's body: “The cause of the death and the fire, was ‘undetermined.’ Undetermined? That’s the [prosecution's] best-case scenario?”

True enough, the Arcadia Avenue fire has never been ruled as arson, though prosecutors point out that accelerants could have entirely burned away since the fire was so hot.

Mero is likely to remain on trial for two weeks, as the case involves two different murders and a host of witnesses. If convicted on both murder counts, Mero is likely to spend the rest of his life in prison.