Updated

Authorities say a struggle with police contributed to the death of a Massachusetts man who became unresponsive after his arrest at a sobriety checkpoint.

The Essex District Attorney's office said Tuesday an investigation found that a heart condition and high blood pressure also contributed to the Nov. 26 death of 45-year-old Kenneth Howe.

The district attorney says he finds no probable cause that police used excessive force.

Police say Howe struck a trooper and was subdued after a foot chase, then became unresponsive while being booked at the state police barracks. He was pronounced dead at a hospital.

Howe's family filed a federal civil rights and wrongful-death lawsuit in January after a medical examiner ruled that the death was a homicide.

A family lawyer says a statement will be issued Wednesday.