UPDATED | June 29, 2015 5:30 PM

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IRVING (CBSDFW.COM) Two brothers pulled from an Irving apartment swimming pool last Wednesday have died.

The Irving Police Department says Treshawn Smith, 9 and Anthony Smith, 11 passed away around 9:15pm Sunday.  Both had been on life support.

Their 10-year-old sister, August Smith died shortly after being pulled from the pool last Wednesday at the Oak Villas Apartments, in the 2300 block of North MacArthur Boulevard.

Irving police detectives say the children’s mother, Patricia Allen, had taken five of her kids to the pool. The children, ages 3, 6, 9, 10 and 11, along with their mother were playing in the pool. As the mother was preoccupied with the two younger children, the three older children went underwater.

Neither the children nor the mother knew how to swim. An apartment maintenance man and others responded to the mother’s cry for help and began a rescue effort.

At this point, detectives are investigating the incident as an accidental death case; however, if the facts and circumstances support that a crime has occurred, the case will be referred to the Dallas County District Attorney’s Office.

The City of Irving revealed last Thursday the apartment pool passed its most recent inspection in November of 2014.

However, the ITeam discovered a history of inspection reports and citations connected to the pool’s water quality, fencing and life saving devices. The city cited managers in July of 2014, noting that it was for a lack of water clarity. Reports noted similar problems in 2013 and 2012, when the pool drain was not visible.

In June of 2013 a citation gave property managers 48 hours to a ring buoy, pole with a hook, and clear up the water. Additional reports last year noted problems with large gaps in the fencing and a gate that was not self latching.

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