A Wisconsin man who was pronounced dead by paramedics after collapsing at his Milwaukee apartment began to move his limbs and breathe just before he was going to be taken to the morgue.

Thomas Sancomb's girlfriend had not been able to reach him for two days so she called police Tuesday asking for an officer to check on him at his home in a high-rise building.

A fire department officer entered the 46-year-old's apartment with the building manager and found the man collapsed at the end of his bed, according to the heavily redacted report from the Milwaukee County Medical Examiner.

Thomas Sancomb (far right) was pronounced dead by paramedics after collapsing at his Milwaukee apartment

About 50 minutes later, Sancomb had 'spontaneous respirations' and began moving his left arm and right leg

The officer called 911 and paramedics from the Milwaukee Fire Department arrived and found Sancomb 'cold to the touch and in rigor' and did not attempt to resuscitate him, the report said.

Sancomb was pronounced dead at 2.10pm at the apartment, forensic investigator Genevieve Penn wrote in the report.

Penn then called Sancomb's brother, John Sancomb, to inform him of the death and an autopsy to determine the cause of death was requested.

A transport team arrived to take the body to the morgue, but at about 3pm Sancomb had some 'spontaneous respirations' and began moving his left arm and right leg,

No pulse was evident, but Penn summoned paramedics back to the apartment and called the family.

Sancomb's pulse returned and he was taken to Columbia St. Mary's Hospital, where he was admitted to the intensive care unit.

His diagnosis at the hospital was redacted from the report.

The Milwaukee Fire Department is investigating the incident, WISN reported.

Assistant Chief Gerard Washington said: 'We're doing an internal investigation to make sure that everything we did followed protocol.

'It's an active investigation, so I can't comment in detail.'

Hospital spokesman Evan Solochek said no information could be disclosed because of federal privacy laws.

Sancomb's brother told the medical examiner that his sibling had a drink and a cigar every once in a while but did not use street drugs.

He told The Associated Press that his brother is improving every day and was concerned he wasn't walking well when he last saw him two weeks ago.

'Thomas' health is the most important thing we're focusing on right now,' he said, declining to talk further about the incident.

The medical examiner's office declined to comment on the case.

The Milwaukee Police Department only said officers responded to a welfare check and found the man unresponsive in a bedroom.