SAN ANTONIO — An anonymous tip led police to a man they are now charging in the murder of two adults more than a year ago.

The murder in question happened Sept. 30, 2018 at an apartment complex in the 8600 block of Fairhaven. When officers responded to the original shooting, they found Nicholas Milanovich, 23, and Julia Wright, 21, shot. Milanovich was alive when officers arrived by later died at the hospital.

The original investigation found 9 mm bullets at the scene.

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According to court records, the tip told officials about Jilson Duban Avelar-Rodriguez, 20, who they said lived with his girlfriend.

Investigators went to the girlfriend's apartment, who agreed to allow them to search it. During the search, officials say they found 9 mm ammunition in the apartment, which is common but it was made by the same manufacturer.

Officials say months later they learned of a missing lock box, which was given to one of the victims by a Methadone clinic to take medicine on the weekends.

The investigating officer reported they remembered seeing this lock box at the girlfriend's apartment during the initial search, so decided to make a return.

Court records say the girlfriend agreed to another search, but not until after she cleaned up her bedroom. After she had done so, officials say they searched and found the lock box hidden behind a washing machine in the closet. According to the affidavit, the same code assigned to the victim unlocked the lock box.

Now, with the evidence, officials say they confronted Avelar-Rodriguez at the Federal Immigration Detention Facility in Pearsall, Texas. Court records say he initially denied the accusations, but once he was confronted with the evidence, he admitted to shooting the two victims after breaking into the apartment.

Avelar-Rodriguez was being held in the detention facility for illegally entering the country, he's now facing a capital murder charge.