SAN FRANCISCO (KCBS)– San Francisco’s police department is widening its probe into offensive text messages by its officers that included racist and homophobic slurs.

KCBS and Chronicle Insider Phil Matier reported in Tuesday’s Matier and Ross column that at least 10 additional officers are now under investigation by the department’s internal affairs unit.

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San Francisco Public Defender Jeff Adachi confirmed investigators are already reviewing more than a decade of text messages by the original four police officers accused of using racist and homophobic slurs in text messages.

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“We estimate that there will be as many as 1,000 cases that will have to be reviewed. I met with District Attorney George Gascon and we agreed to go back at least 10 years,” Adachi said.

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Police Chief Greg Suhr has not identified the additional officers that are now under investigation, but told the Chronicle he expects the investigation to take about a month.