The US navy has used underwater drones, warships and inflatable vessels to gather all of the pieces of the massive Chinese spy balloon a fighter jet shot down off the coast of South Carolina.

In the newest images released by the Navy on Tuesday, sailors from Explosive  Ordnance Disposal Group 2 are seen leaning over a rigid hull inflatable boat and pulling in pieces of the balloon’s white outer fabric and shell structure.

The head of US Northern Command, General Glen VanHerck, said the teams were taking precautions to safeguard against the chance any part of the balloon was rigged with explosives.

This image provided by the U.S. Navy shows sailors assigned to Explosive Ordnance Disposal Group 2 recovering a high-altitude surveillance balloon off the coast of Myrtle Beach (US navy/AP)

The balloon was an estimated 200 feet (60 metres) tall and was carrying a long sensor package underneath, which Mr VanHerck estimated was the size of a small jet.

The navy is also using ships to map and scan the sea floor for all remaining parts of the balloon, so US analysts can get a full picture of what types of sensors the Chinese were using and to better understand how the balloon was able to steer.

The balloon debris is scattered in waters that are about 50 feet (15 metres) deep, but stretch across a vast area, Mr VanHerck said.

A navy warship, the USS Carter Hall, is heading the recovery effort, aided by three Coast Guard cutters – the Venturous, the Richard Snyder and the Nathan Bruckenthal – as well as the USNS Pathfinder, an oceanographic survey ship. A salvage ship is expected to arrive on Wednesday.

The Pentagon said on Tuesday that defence secretary Lloyd Austin requested a secure call with his Chinese counterpart, minister of national defence Wei Fenghe, on Saturday after the balloon was shot down.

China declined the request, said the Pentagon press secretary.