GERMANTOWN, Md. -- A man suspected of raping three women between 2007 and 2011 has been arrested by Montgomery County police.

Marlon Michael Alexander, age 39, of Dairymaid Drive in Germantown, was arrested Thursday for attempted sexual offense and three first-degree rapes in Gaithersburg and Germantown. He was also charged with first-degree burglary in connection to those four crimes.

According to police, Alexander broke into the victims’ homes before assaulting them.

The first assault, on August 11, 2007, allegedly happened around 1 a.m. Police say Alexander broke into the home of a 25-year-old woman in a block of Lost Knife Circle in Gaithersburg and then threatened to shoot the victim if she did not perform a sexual act and a struggle ensued.

Alexander then allegedly fled the scene. Montgomery County Police Chief Thomas Manger said Alexander's DNA was recovered at the scene.

Three years later, on June 19, 2010, at around 3 a.m., officers say Alexander then allegedly broke into the home of a 68-year-old woman in a block of Beaconfield Terrace in Germantown. Manger said Alexander held a weapon to her head and raped her. He also said Alexander's DNA was found at that scene.

Montgomery County Police say they believe Alexander also went back to that same victim's home to rape her on January 5, 2011, just before 1 a.m.

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The final alleged assault linked to the Montgomery County Police Department's investigation of Alexander occurred on August 21, 2010 just after 4 a.m. Officers say the suspect broke into the home of an 86-year-old woman in a block of Father Hurley Boulevard in Germantown. In that incident, Manger said Alexander had a pair of scissors while he raped the victim before hitting her with his hands.

"Detectives believe it is possible Alexander committed additional sexual assaults," Manger said.

The DNA recovered at each scene was found to match the previous assaults.

Alexander’s DNA was obtained via search and seizure warrant.

Clifford Carter, Alexander's neighbor, was at home when officers arrived to collect the DNA sample. He said he was surprised, Alexander, who is married with kids, was named as a suspect in the

case.

"Talking to him, I thought he was a pretty cool dude," Carter said. "We talked about sports. He came and went and did family stuff with his kids. Then, when I looked at the news on the website and saw all the stuff, I was like, 'whoa'."

On September 13, the DNA samples provided by Alexander were sent to a lab for analysis and matched the DNA at the four assault locations.

Alexander was arrested at a grocery store in Germantown on Thursday and is being held without bond.

His bond review hearing will happen Monday.

Manger said a Virginia company named "Parabon" helped with the investigation. Parabon buys the rights to data from companies that do genetic analysis.

"They basically have a database of a lot of DNA that has been submitted," Manger said.

Manger said his department gave Parabon the DNA it collected from the four crime scenes connected to Alexander. He said the company then conducted a comparable analysis with its data and provided Montgomery County with several names of individuals who had DNA close to the suspect.

Police then spoke with a woman in Georgia who was also identified from Parabon's analysis who said she had distant relatives who lived in Montgomery County.

A Montgomery County officer, who Manger said is well-versed in documenting family lineage, was able to use that information to further determine that Alexander should be a suspect in the case.