Brownsville, TX (KRGV) — A candlelight vigil will start at 5:45 P.M. at Tres Angeles Park Thursday to remember three children who were killed by their father 23 years ago, the Cameron County District Attorney’s Office announced.

Since his 2003 arrest, John Allen Rubio has said he killed 3-year-old Julissa, 1-year-old John, and 2-month-old Mary Jane because they were possessed by demons. Prosecutors said Rubio and his common-law wife, Angela Camacho, killed the children because they could not financially support them. Camacho is serving a life sentence for the crime.

 Rubio is set to be executed Thursday sometime after 6 p.m.

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The district attorney’s office said it will hand out 150 candles to those attending the vigil, and someone will stay on standby for a call confirming Rubio’s death.

Once that call comes, a representative will ask people to light their candles in honor of the children. The park was built to remember them and other crime victims and sits on the grounds of the apartment building where the children once lived and where their father killed them. People who did not know the family still remember how deeply it affected them.

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“That was really tragic. We couldn't believe the extent of the tragedy,” Brownsville resident Dora Cain said.

Cameron County District Attorney Luis Saenz said the long wait through the legal process has been emotional for the children’s family. Saenz said the community still has not forgotten the crime and the loss.

READ MORE: Brownsville community reflects on 2003 child murders ahead of Rubio execution

This is a developing story, check back for updates.

WATCH ECHOES FROM BROWNSVILLE - THE RUBIO MURDERS, A CHANNEL 5 NEWS ORIGINAL DOCUMENTARY THAT EXAMINES THE SHOCKING CRIME