Montgomery County Police Chief Tom Major announced on Monday the arrests of four individuals in connection with the murder of middle school principal Brian Betts.

“We believe the motive of this crime was most likely robbery,” says Major, adding that police have surveillance footage showing the suspects using several credit cards taken from the slain principal’s home.

Major says the alleged killers contacted Betts through a telephone chat line. “It’s been described as a sex chat line,” he says.

Sharif Tau Lancaster, 18, of the 5300 block of 5th Street NW, and Alante Saunders, 18, of unknown address, were each charged with first-degree murder.

Major says police found Lancaster’s prints inside Betts’ home and found Saunders’ prints inside the slain principal’s car.

Police have also arrested Lancaster’s mother,  Artura Otey Williams, 46, on stolen property charges related to the case.

Another suspect in police custody has yet to be charged.

WaPo reports that police have video of Williams using the slain principal’s credit card at a Giant food store on East West Highway in Silver Spring on April 16.

Betts was a beloved principal at the District’s Shaw Middle School at Garnet-Patterson. He was found fatally shot in his Silver Spring home on April 15. There were no signs of forced entry.

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