AS a four-year-old girl desperately paddled towards a life jacket amid the wreckage of SIEV 221, a man bobbing in the monstrous Christmas Island swell grabbed it and then kicked her away, an inquest has heard.

Local Australian Federal Police officer, Special Constable Shane Adams, stood on the cliffs at Rocky Point on December 15, trying to help the 89 asylum seekers and three crew members whose boat had smashed into rocks.

He spotted the girl after the boat broke apart trying to dog paddle towards a life jacket he had flung into the sea.

Const Adams said he then noticed a man aged about 35 in the water nearby.

"He reached out and grabbed the life jacket, pushed out with his right foot and struck the young girl on the shoulder, pushing her back," he told the inquest on Christmas Island.

That was the last time Const Adams saw the girl.

Before the boat was torn to pieces amid the backwash at Rocky Point, Const Adam said he saw a woman stretching over the railing of the starboard side of the vessel holding a baby in a nappy.

The woman was screaming, 'take my baby, take my baby.'

It was what Const Adams described as a "freak swell" of about five to six metres which destroyed the wooden vessel and caused the roof to collapse.

Underneath the ship's ruptured verandah lay an elderly man, he said.

Const Adams also told the inquest he stood on the razor-sharp rocks and threw down a rope which a man grabbed hold of, but when the asylum seeker got within 10cm of safety he fell back and was not seen again.

The vessel had originally come near the shore under power but while manoeuvring in the rough seas, a blue drum fell off the boat leaking diesel into the sea.

"In my opinion the vessel had now lost its fuel supply," Const Adams said.

"At the same time the smoke exhaust stack started to puff and then stopped ... and the vessel ceased moving forward."

Fellow AFP officer Constable Brett Ford helped bring the dead bodies ashore at Ethel Beach on the other side of the island.

From about 10.30am, bodies of men, women and children were continually unloaded, Const Ford said.

But soon they ran out of body bags and had to wrap the deceased in black, plastic sheets.

This continued until about 4pm later that day.

Claire O'Connor, the lawyer acting for survivors and the families of dead, told the inquest her clients had nothing but praise for locals who rushed to the cliffs that day.

"Many owe their lives to many of the community members who helped, who pointed out to the navy where people might be in the water and provided medical services," Ms O'Connor said.

"It was far beyond what they were expecting and are extremely grateful."

Earlier in the day, Ms O'Connor put to Sergeant Adam Mack, from the West Australian Water Police who coordinated the search and rescue operations, that a factor in the deaths was the poor condition of the boat which she said was "practically a floating coffin".

Sgt Mack replied: "It was an unseaworthy vessel and did not have the appropriate safety equipment and due to other circumstances it caused the vessel to break down, the motor to lose power and crash into the cliffs."

The inquest before WA Coroner Alastair Hope continues.