MIAMI (AP) — Police said Tuesday they charged a Miami man with first-degree murder after he confessed to suffocating his estranged wife and her two young daughters following an argument at a mall.

Alberto Luis Sierra and Gladys Del Carmen Sierra got into a fight on Nov. 10 when Sierra pulled out a knife and “harmed” his 29-year-old estranged wife, according to an arrest report. Miami-Dade Police did not describe her injuries from the argument.

Sierra, 28, then took Gladys Del Carmen Sierra and her four and six-year-old daughters back to the house, where he locked the girls in a bedroom and forced Gladys into the master bedroom. He then suffocated her with a plastic bag and sexually assaulted her, authorities said.

Sierra later suffocated sisters Daniela and Julia Padrino with a plastic bag and also sexually assaulted one of them afterward, according to the arrest report. Miami-Dade Police said one of the girls was sleeping when she was suffocated.

The girls are not the defendant’s biological children. Police say the Gladys’ 6-year-old son was safe with his grandmother.

Sierra was charged with three counts of first-degree murder and sexual battery on an adult and on a child under 12. It’s unclear if he had retained a lawyer.

A neighbor complained of a foul odor coming from the home a few days later and found Gladys Machado in a closet next to her two girls.

Neighbors said Sierra had recently been released from jail.

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