MIAMI (CBS4) – Miami Police are looking for an armed man who they say assaulted a woman and robbed a man selling some personal belongings on an Internet marketplace.

Police say the victim, Angel Diaz, put his Xbox game console up for sale on the site on December 8, 2011. He immediately received a response via text message from an interested buyer and immediately set up a meeting to execute the sale.

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Diaz told police that once the suspect arrived at Diaz’s home, he pulled a gun and demanded all of his personal belongings. The suspect also demanded everything from the Diaz’s friend Mauricio Giraldo.

Police say Diaz’s mother entered the room after hearing the commotion and was pistol whipped across the head.

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The victim’s mother fled to a nearby bedroom for safety and was followed by the suspect. Giraldo ran out of the house for help.

Upon seeing Giraldo run out of the home, the suspect fled in a possibly older model Nissan Maxima.

The suspect is described as a man in his 20’s with a goatee. He stands approximately 6 feet tall and weighs roughly 180 pounds. He was last seen wearing a grey shirt and black pants.

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Anyone with information is urged to contact The Miami Police Department’s Robbery Unit at (305) 603-6370 or Miami-Dade Crime Stoppers at (305) 471-8477 (TIPS).