Police on Tuesday found four people dead of gunshot wounds in a Colorado home and one hypothesis being considered is that one of them killed the other three and then committed suicide.

The two men and two women found dead were apparently related, Weld County Sheriff's Office spokesman Tim Schwartz said.

The case has attracted significant public attention because the country still has not emerged from the emotional turmoil caused by the massacre of 26 people - including 20 children - at a Connecticut elementary school by a 20-year-old man who first killed his mother and finally killed himself.

Colorado police have not identified the people found dead on Tuesday, but a woman named Edy Silva said that two of them were her nieces Beatriz and Maria Cintora Silva, media outlets said.

Edy Silva, who came to the crime scene located about 55 kilometers (34 miles) north of Denver, said that Maria had gotten married about five months ago and was living in the house with her husband.

Shortly before dawn, the Weld County Sheriff's Office received a telephone call from a women asking for help and screaming "no, no, no."

The dispatcher listened and heard gunshots whereupon a man picked up the telephone and said he was going to kill himself, after which a final shot was heard.

Police were dispatched to the house in Longview and found the two women - one of whom appeared to be a teenager - and two men dead. EFE