A man is dead after he and a woman were found bound and gagged in the middle of a street in San Francisco's Bayview District Sunday night.

A motorist driving on Brussels Street saw the two people lying on the road and called the police around 8:30 p.m., San Francisco officer Albie Esparza told NBC News.

Both were found bound and gagged. The man, believed to be in his early 20s, was unconscious. The woman, also believed to be in her early 20s, was "out of it," Esparza said. The pair were taken to the hospital, where the man died and the woman remains in critical condition.

Police are awaiting a medical examiner's report to determine what caused the trauma on the male victim. Esparza said it could have been a gunshot wound or trauma caused by blunt force.

"No one saw or heard anything," Esparza said, adding that investigators are still trying to determine if the two victims had been attacked elsewhere and dumped on Brussels Street. Police are hoping the female victim will be able to speak with them soon.

Esparza said the neighborhood the two were found in is "pretty quiet."

"It's just your typical working-class neighborhood," he said, adding that investigators are canvassing the area to see if any of the homes had video surveillance and are asking the community to come forward with information.

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