Police officers stand outside an apartment where seven people were shot and killed on Christmas day in Grapevine, Texas, December 25, 2011. [Photo/Agencies]

HOUSTON - Seven people were found dead in a Dallas-area apartment after police in Texas, US entered the unit on Sunday, according to local media reports.

Police said that the four women and three men have apparently been shot.  

"All victims appear to have gunshot wounds," Grapevine police said in a statement.

Police responded to the address "in reference to a 911 open line," said the statement.

The victims appeared to be related, Grapevine Police Sgt. Robert Eberling was quoted as saying.

All the dead were found in the same adjoined kitchen and living room area of the apartment in Grapevine, about 25 miles northwest of Dallas, police said.

Police are now investigating the cause of the incident.