Updated

The medical examiner has ruled that the chokehold of a police officer on a New York City man last month caused his death.

Medical examiner spokeswoman Julie Bolcer said Friday that Eric Garner's July 17 death has been ruled a homicide.

Bolcer says his death was caused by "the compression of his chest and prone positioning during physical restraint by police." She says asthma and heart disease were contributing factors.

Garner's videotaped confrontation with police has caused widespread outcry, and Attorney General Eric Holder has said the Justice Department is "closely monitoring" the investigation into his death.