The suspect in the fatal shooting of three police officers in York County , Pennsylvania, on Wednesday has been identified as 24-year-old Matthew James Ruth.

York County District Attorney Tim Barker identified the fallen officers as Mark Baker, Cody Becker and Isaiah Emenheiser.

Police sources say Baker was a former Philadelphia highway patrol officer.

Two other police officers were shot and remain in the hospital. Barker said the two officers are critical but stable.

The shooting happened on a farm in North Codorus Township in York County just after 2 p.m. Wednesday.

Pennsylvania State Police said the investigation began as domestic in nature.

Law enforcement sources tell CBS News Philadelphia that police were at the North Codorus farmhouse to serve a warrant when Ruth fired upo

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