Authorities on Tuesday said a San Jose man confessed to killing two people in separate incidents along the Guadalupe River after turning himself in to a police officer on patrol over the weekend.

Marcelino Castro allegedly confessed to the crimes after he flagged down an officer at about 5:14 p.m. on Saturday and said he had killed a person in the area of Lelong Avenue and Alma Avenue, according to a statement from the San Jose Police Department.

Officers responded to the area and found a “deceased male” and took Castro into custody, police said. During questioning, Castro allegedly revealed he had committed a second killing in the area of Autumn Parkway and Coleman Avenue, roughly 2.5 miles from the first crime scene.

Police responded to the location and found another person dead. Authorities gave no further details.

It remains unclear when the killings took place and what, if any, weapon was used. Police said the motive and circumstances in each case are still under investigation.

Castro is being held in the Santa Clara County Main Jail on suspicion of two murders.

The homicides are being investigated as the city’s 20th and 21st of the year. Anyone with information about the killings is asked to contact the department’s homicide unit at 408-277-5283.

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This article originally published at San Jose man turns himself in, confesses to two killings, police say.