Police in Langley, B.C., say an autopsy is needed to determine exactly how a suspected bank robber died after being Tasered on Tuesday.

The 49-year-old man was naked and bleeding when he was jolted at least once by RCMP officers. Police were trying to subdue him after he had fallen from the second floor of his home.

The suspect had apparently already suffered severe chest injuries before he crashed naked through the window and fell to the ground.

The incident began Tuesday morning, when the man was followed to his Langley home after being allegedly seen robbing a nearby Royal Bank.

RCMP Cpl. Peter Thiessen said a Taser was used after a police dog failed to engage the man and he tried to re-enter the house, where his common-law wife was still inside.

He collapsed after the Taser was used.

Thiessen said using the conductive energy weapon was a split-second decision and considered appropriate because the man was thought to be armed and therefore a threat to a woman inside a residence where he had taken refuge.

"They [police] made this decision because it was thought to be in the best interests of the public and the officers involved,'' he said.

The man was transported to hospital, where he was pronounced dead.

Thiessen could not say how soon the man died after being Tasered. His common-law wife was arrested at the scene, but no charges have been laid.

B.C. police have come under fire recently for using Tasers.

Last week, Vancouver police defended their use of a Taser stun gun on a teenage mom, saying officers took the action to save the life of a critically ill one-month-old baby.

More than 70 Canadian police forces currently use Tasers, which were approved in December 2001 by Giuliano Zaccardelli, who was commissioner of the Mounties at the time.

Since then, the stun guns have been indirectly linked to about 20 deaths, and Zaccardelli has publicly stated that Tasers should be decommissioned.