(STMW) — Two brothers who were found dead at the site of a townhouse under construction Tuesday morning in southwest suburban Lockport were shot, autopsies have found.

David Ceja-Sanchez, 35, and Marco Ceja-Sanchez, 37, each suffered a single fatal gunshot wound, the Will County coroner’s office announced Wednesday evening.

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The Aurora residents were discovered when their coworkers showed up at the work site about 6:30 a.m. in the 16100 block of Coneflower Drive, according to Lockport police and the coroner’s office.

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Their deaths are being investigated as a double homicide, authorities said. No one was in custody.

The Will-Grundy Major Crimes Task Force is assisting with the investigation.

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