Border security has a new, computerized face at Vancouver International Airport, and that has some people worried.

It's called automated border clearance; you just swipe your passport or identification, feed in your customs declaration, and you're on your way.

The idea is to more efficiently process Canadian citizens and permanent residents.

The machines will be tested in a two-year pilot project that was quietly put into place by the federal government two months ago.

There was no official announcement, although a description of the new measures was posted on the government website.

And neither the government nor the Border Services Agency returned calls for comment.

The border guards' union says it's worried the new system means decreased security.

"I'm alarmed, because…somebody's coming through without seeing an officer at all," Sue Neumann of the Customs and Immigration Union told CTV News.

The union agreed to the machines on the condition the freed-up guards could rover through the arrivals area, but that hasn't happened.

And that's not the only concern.

"Sometimes, information is misread, or information is put in that, if an officer were to have read it, would not have been accepted," Neumann said.

International relations professor Michael Byers agrees. He says that machines just can't replace people.

"A border guard can sense whether or not someone is nervous. They can see whether there's a twitch on the face, or perspiration on the forehead. It's very difficult for a machine to do that," he said.

The opposition Liberals only found out about the new system when CTV News called.

A surprised Liberal MP said he'll take concerns about the machines to the House of Commons.

"I'm going to want this to be studied at committee. I'm going to want the opportunity to look at these measures and actually ask questions about how much it's going to cost, how effective it's going to be, what backup plans are going to be in place," Liberal public safety critic Mark Holland said.

With a report from CTV British Columbia's Jon Woodward