A 36-year-old woman and her three children were reportedly killed by the woman 's incarcerated boyfriend during a trip to see him in prison . 40-year-old Domingo Villa Arellano , who is an ex-cop , allegedly carried out the slayings on March 15 inside Puente Grande prison , El Excelsior reported . Puente Grande is a maximum-security prison in Jalisco , Mexico . A 36-year-old woman and her three children were reportedly killed by the woman 's incarcerated boyfriend during a trip to see him at Puente Grande prison ( seen in this file photo ) According to El Excelsior , Villa Arellano said he stabbed his girlfriend Ericka Isela Velazquez Cocula 's chest with a weapon during a verbal dispute . Villa Arellano reportedly said he used a metal object from his time spent making handicrafts . El Excelsior reported that at the time , Villa Arellano was furious over the couple 's two children saying their mother was treating them poorly . Villa Arella went after the children and his girlfriend 's 17-year-old daughter , El Excelsior reported . The girl got away and died at a hospital , according to the newspaper . Villa Arellano reportedly later tried to kill himself and was hospitalized . El Excelsior reported that the 40-year-old has been behind bars since 2006 over killing a girlfriend and sexually abusing the woman 's daughter . Villa Arellano has been behind bars since 2006 over killing a girlfriend and sexually abusing the woman 's daughter ( file photo )
40-year-old Ericka , who is an ex-cop , allegedly carried out the slayings on March 15 inside Puente Grande prison . Villa Arellano admitted to stabbing his girlfriend Domingo Villa Arellano Isela Velazquez Cocula 's chest with a weapon during a verbal dispute . Villa Arellano was furious over the couple 's two children saying their mother was treating them poorly . He went after the children and his girlfriend 's 17-year-old daughter .