HOUSTON — Harris County Sheriff's deputies rappelled off a bridge for the first time on Thursday, according to members of the SWAT team

Thursday's Greenpeace protest, in which activists dangled more than 200 feet in the air off the Fred Hartman bridge, closed the Houston ship channel. SWAT team members eventually rappelled down, secured each protester, and brought them to land to be arrested.

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Deputies said some of the protesters were resistant as they tried to get them down. Others were not.

”This was unlike anything we’ve done before," said Deputy Scott Cogburn. ”When you’re coming off that edge, it’s nerve-wracking. Once you get down, it’s almost peaceful.”

Deputies said the number of cumulative hours they spend training to rappel is better measured in days.

”Unfortunately, we have not trained over the side of a bridge. Normally, we’re on the side of a building," said Deputy David Rhen.

Deputy Rhen said not having a surface to push off of increased the difficulty of the operation.

”There was a 30 mile an hour wind that was pushing you underneath the bridge," said Dep. Rhen. ”You’re assuming a lot of liability in conducting this operation."

Deputies said each retrieval took about an hour on average. Each time they would go over the edge, they did not know if the protester they were going to help would be resistant or not. Some were. Others cooperated.

For Deputy Luther Eta, Thursday was the first time he had ever rappelled in a live, non-training situation.

”Deputy Cogburn said ‘hey, there’s another one up there, you want it?’ I was like, ‘I guess I’ll go if everyone else is going," Deputy Eta said with a laugh. :I guess after seeing the repetition, the confidence in our guys, the fire department helping out, that really calmed me.”

Eta had the added difficulty of performing his retrieval at night, around 10 p.m. 

Deputies said they got some remote help and advice from the New York City Police Department in their first time through the operation. Baytown and Houston Fire Departments, Houston Police, Precinct 1 Constable's Office deputies, the Coast Guard and others helped on scene.