KNIGHTS LANDING, Calif. — The man accused of hitting and killing three people as they slept in their Knights Landing trailer is in the country illegally, Immigration and Customs Enforcement officials confirmed Tuesday.

Sutter County Sheriff’s Office spokesman Undersheriff Scott Smallwood said 38-year-old Jose Pacheco, 34-year-old Anna Pacheco and their 10-year-old son Angel Pacheco were killed Saturday night when Ismael Huazo-Jardinez crashed his truck into the trailer in which they were sleeping.

Mariana, the Pacheco’s 11-year-old daughter, was taken to the hospital in critical condition. On Tuesday her condition was updated to "fair," according to Carole Gan, the UC Davis Health spokesperson. 

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Huazo-Jardinez was arrested Saturday night for a suspected DUI and taken to Rideout Emergency Room for moderate injuries. He was booked into the Sutter County Jail for vehicular manslaughter and felony DUI but was released Sunday after posting $300,000 bail.

On Tuesday, ICE confirmed that Huazo-Jardinez is an "illegally present Mexican national" and is now in the department's custody pending immigration proceedings.

In the statement, ICE wrote that Huazo-Jardinez was previously caught by Border Patrol agents while in Arizona, and granted voluntary return to Mexico in February 2011.

Non-criminal aliens from Mexico are eligible for voluntary return, which means that the person admits that they are in the country illegally and agree to return as soon as possible.

ICE believes that Huazo-Jardinez returned to his home country but at some later point, returned to the United States.