MILWAUKEE, Wis.(WHBL) - Milwaukee Police said a robbery suspect collapsed and died while being driven to jail in a squad car. The man’s mother doesn’t buy the explanation, but police said the whole thing’s on video. It all started yesterday, when an officer saw a masked man rob two people near a north side Milwaukee intersection. A foot chase ensued, and the alleged robber was found hiding in a yard. His mother, Sonya Moore, identified the man as Derek Williams. Police spokeswoman Anne Schwartz said he was arrested without incident. And while riding in the back of the squad car, Williams fell on the back seat. An officer checked for a pulse, and three officers then began life-saving efforts until Fire Department rescuers arrived about 10 minutes later. Those rescuers tried for another 28 minutes to save Williams’ life, but he died at the scene. Moore told W-T-M-J T-V in Milwaukee that it didn’t seem right that her son just stopped breathing – and she suspects the officers hit him. Schwartz said a full autopsy would be performed on Williams, and Milwaukee prosecutors will join the investigation. Meanwhile, the officers involved are on administrative duty for now.