Houston police are still looking for answers following the gruesome murder of three people in northwest Houston Sunday.

Witnesses say they heard gun fire at the apartment complex The Pines of Northwest Crossing and ran to help.  Inside the apartment they found two women and a man shot to death, execution style.

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Police say four armed men broke into the apartment and began firing.  The men were wearing all black, ski masks, and were carrying rifles.  Police say they found shell casings from a pistol, a shot gun, and a rifle.

HPD is asking for the public's help in solving this murder.  Anyone with information on this case are asked to call the HPD's tipline at 713-308-3600 or call Crime Stoppers at 713-222-TIPS.