Boo, the young grizzly that escaped from a refuge in southeastern B.C. three weeks ago, has busted loose again — this time by knocking down a huge steel door, storming two electrical fences and climbing a four-metre barrier.

The four-year-old captured hearts across the country with reports of his first escape on June 5 from the Kicking Horse Resort near Golden. That time, he dug his way under a fence after catching the scent of a wild female bear.

After the two were spotted roaming the mountainous area near the wildlife refuge, Boo was recaptured on June 23 and returned to his nine-hectare enclosure. Staff at the refuge put him in an extra secure area behind a 181-kilogram steel door, two layers of electrical fencing and another, higher fence.

But a resort spokesman, Michael Dalzell, told CBC News that Boo got loose for a second time a day later.

"He basically broke out of Fort Knox," Dalzell said.

He said the bear appeared to be in good spirits just hours before his second breakout.

"We woke up and Boo was not in his winter denning area, and that's the area where we had kept him, which for us was unthinkable," Dalzell said.

Boo has not been seen since his latest escape, he said.

Resort officials had said they planned to neuter Boo to take away the young male's sexual urges,which led him to escape the first time — but they didn't have time to put him under the knife before he got away again.

Boo orphaned by hunter

The young bear was orphaned when he was was seven months old, after a hunter shot his mother along the Barkerville Highway in the Cariboo in 2002.

He and his brother Cari — named after the region where they were found — were taken to the Grouse Mountain Wildlife Refuge before being shipped to the Kicking Horse Resort.

Cari died during hibernation at the refuge in 2004.