Three people were killed in an apparent execution-style murder at an apartment complex in the U.S. city of Houston Sunday, local media reported. Police rushed to the scene in northwest Houston after receiving calls Sunday night and found two Hispanic women and a man shot to death, the Houston Chronicle reported. Preliminary investigation found as many as three suspects, possibly wearing masks, burst through the door of the apartment around 6:15 p.m. CST Sunday. The victims had been shot multiple times with more than one weapon, police said. Houston police called the triple murder an execution-style shooting because all the victims were shot at close range. The gunmen remained at large and the police is carrying out a manhunt. Investigators now don't have a motive for the killing. The apartment appeared ransacked, but investigators said there was no way to know if anything was missing. Police said they had responded to a call alleging prostitution at the address at an earlier date, but that no arrests were made, according to the report. No other details are available now.