An unidentified man was found stabbed to...

An unidentified man was found stabbed to death in the hallway of a downtown San Diego hotel Wednesday morning, the third homicide victim in three days within a five-block area.

The three killings are not believed to be related, police said.

Police found the body of the man on the second floor of a hotel in the 1400 block of K Street shortly before 4 p.m., said Lt. Dan Berglund. The man was described as Latino, between 15 and 20 years old and wearing a satiny-blue jacket, blue work pants, white socks and black shoes.

Witnesses told police they saw four men break into the hotel through a second-floor window, apparently in search of drugs, earlier that morning, Berglund said.

“Witnesses heard what sounded like a struggle and arguing, and what sounded like a fight” before the stabbing, he said.

On Monday, 67-year-old Prospero Francis was found beaten and stabbed to death in a downtown hotel room in the 500 block of 12th Avenue, where he had lived for the past 30 years, police said. His room had been ransacked, leading police to believe the motive was robbery.

On Tuesday, Gilberto Torres, 25, was found shot to death on a sidewalk in the 1600 block of Island Avenue, police said.

Berglund said the the slayings are not connected.

“There are no similarities,” he said. “There is really no connection.”

The Christmas morning shooting happened after an argument, according to witnesses, and although a motive has not been established in the Wednesday morning slaying, a different weapon--a knife--was used, he said.

Police are still investigating the three cases and have made no arrests.