Leyla Monserrat Lares Becerra mother Carmen Angélica Becerra Valencia

Leyla Monserrat Lares Becerra (left); and her mother Carmen Angélica Becerra Valencia.Credit : La voz de Sonoyta/Facebook; TelediarioMx/Youtube

NEED TO KNOW

Leyla Monserrat Lares Becerra, 15, was lured and killed by two teens in Sonoyta, Mexico, in September 2025
The attackers, ages 13 and 15, confessed to the crime, which was reportedly motivated by romantic rivalry
The light sentences for the teens sparked outrage as Leyla’s mother mourns her loss and demands justice

A small town in northern Mexico is reeling months after two teens lured their friend with a “surprise” but killed her — and the victim’s mother was later sent a video of the murder.

Leyla Monserrat Lares Becerra, 15, was killed in the northern Mexican town of Sonoyta on Sept. 25, authorities have said, according to local outlets La JornadaEl Universal and Univision.

The Attorney General’s Office of the State of Sonora (FGJE) has said the two attackers, ages 13 and 15, whose names have not been publicly released, confessed to the crime, Univision reported.

According to investigation reports cited by La Jornada, the motive was romantic rivalry.

Our new app is here! Free, fun and full of exclusives. Scan to download now!

The investigation revealed the minors lured Leyla with a surprise they said she would never forget, per Univision and PuenteLibre, which cited the FGJE’s account.

Once at the location where she would later be killed, the assailants tied her to a chair and blindfolded her, according to a clip of video from the incident shared online by Univision.

The video shows Leyla tied up while one of the assailants speaks to her, while another places a rope around her. All three are heard laughing and conversing, La Jornada reported. (In the video, the faces of all three people are blurred.)

The attackers then strangled Leyla with the rope, per La Jornada. (The act itself was blurred in the video published by Univision.)

Leyla Monserrat Lares Becerra

Leyla Monserrat Lares Becerra.La voz de Sonoyta/Facebook

Leyla’s body was found in October, showing signs of decomposition, Univision reported.

Months later, Leyla’s mother received a video of the murder, according to multiple reports. The mother, Carmen Becerra, has reportedly said the killers were harassing her daughter prior to the murder.

In an earlier stage of the investigation, police were reportedly looking at an adult male as a possible suspect, but he was later found dead, La Jornada and Univision reported. PEOPLE is not disclosing his name because he was never officially named a suspect in the case.

¿Qué pasó con Leyla Monserrat? Esto sabemos de la menor que fue asesinada por dos “amigas” en Sonora

Want to keep up with the latest crime coverage? Sign up for PEOPLE’s free True Crime newsletter for breaking crime news, ongoing trial coverage and details of intriguing unsolved cases.

The two girls were sentenced in March: the 15-year-old received two years and 10 months of confinement, while the 13-year-old was sentenced to 11 months of supervised release, sparking outrage over how light the punishments were.

“While my daughter’s murderers can return to their normal lives, I never even got to say goodbye to my daughter,” said Becerra, according to Univision.