READING, Pa. -

Frustrations are mounting as the man accused of murdering a 15-year-old boy in Reading one year ago remains on the loose. Authorities believe the suspect is hiding in Mexico.

Reading police said Jose Espinoza-Diaz slashed the throat of Wilberto Rojas in broad daylight at Douglass and Church streets back on July 19, 2013.

According to investigators, Rojas was walking with friends into a park when Espinoza-Diaz attacked him and ran off. He has been on the loose ever since.

On Saturday, exactly one year after Rojas was killed, Reading police told 69 News that authorities believe Diaz is still in Mexico, and that they are trying to work with Mexican authorities to have him detained and returned to the U.S.

Reading police expressed frustration over trying to work with authorities in Mexico, which Captain Jeffrey Parr called "difficult at best."

An exact motive for the killing was never released by authorities, but they did say it did not appear to be a random attack.

The murder of the boy left family and friends heartbroken. Today, 69 News went to the neighborhood where Rojas lived, and residents there say they won't rest until the suspect is taken into custody.

Anyone with information that could assist police is asked to call Crime Alert Berks County at 877-373-9913.