The demonstration lasted 19 minutes before the U.S. Park Police issued a final dispersal order and began making arrests just before 11:30 a.m. Seven protesters left before being arrested.

Meanwhile, 65 more demonstrators arrested Saturday prepared to be released from jail Monday afternoon.

“We see this pipeline as the biggest environmental test President [Barack] Obama will have before the 2012 election,” said Jamie Henn, a spokesman for jailed protest organizer Bill McKibben’s group Tar Sands Action. “With the stroke of a pen, he’ll be able to end a potential environmental disaster, stop the pipeline and electrify a base of support that hasn’t been enthusiastic about his reelection.”

But Obama was on his Martha’s Vineyard vacation, the eyes of the world’s media were on Libya and the White House protest was getting little coverage in mainstream news organizations.

Among the protesters who avoided jail Monday morning were Jane Kleeb, former head of the Young Democrats and now leader of Bold Nebraska, a grass-roots citizen organizing group. She plans to be arrested Sept. 3. The protests, which began Saturday and are slated to continue for two weeks, are designed to bring attention to the Keystone XL project, which is awaiting State Department approval.

The pipeline would carry oil-sands-based crude 1,700 miles from Alberta, Canada, to refineries in Texas. Besides creating jobs, backers of the project say it’s needed to reduce oil imports from the Middle East. Critics say the project would encourage the use of a dirty fuel, and they have pointed to a series of spills from an existing TransCanada pipeline.

The activists’ plan was to stage a two-week sit-in protest in front of the White House, Henn said, with protesters not facing any jail time for the civil infraction.

The Park Police changed the game plan, Henn said.

“Our original understanding was that this was a post and forfeit situation,” Henn said, explaining that protesters would be detained, required to pay a $100 fine and then released. “That’s how everyone was trained, though they were told to expect the possibility of spending the night in jail. But the Park Police wanted to deter future participants so they decided to keep everyone.”

The first group of 65 was arrested Saturday morning, including McKibben, an author and founder of Tar Sands Action. The next day, Henn said, 45 people were sent out to the protest. Those people were detained and released, he said.

Not all of those who were arrested Saturday were held, said Sgt. David Schlosser, public information officer for the Park Police. About 12 were released. Who gets released depends on various factors, including whether the person has identification or pending warrants.

“We have to follow the rules of the court,” Schlosser said. “It’s a case-by-case basis.”

Among those arrested Saturday was former Army Lt. Daniel Choi, who was previously held after White House protests against the “don’t ask don’t tell” policy. Those arrested this weekend were charged with failure to obey a lawful order.

Volunteer protesters sign up on the organization’s website for a date to participate. So far, Henn said, more than 2,000 people are registered to take part.

“We’re still getting lots of sign-ups,” Henn said. “People are getting fired up.”

Each evening, about 50 protesters go through civil disobedience training, Henn said. The next morning, they are sent to participate in the sit-in at the White House.

The first person arrested during Saturday’s protest, Henn said, was a 23-year-old woman from Wasilla, Alaska.

On Monday morning, the website posted a statement from Gus Speth, who passed along the statement through his wife.

“We the prisoners being held in the Central Cell Block of the D.C. Jail need company and encourage the continuation of the protests against the tar sands pipeline,” Speth said. “Help us stop this disastrous proposal! I’ve held numerous positions and public office in Washington but my current position feels like one of the most important.”

Henn said that as the protests go on and more volunteers show up, he expects the number of protesters sent to the sit-in each day will increase, maybe to as many as 100 people each day.

“It’s no small thing to shut down Pennsylvania Avenue,” Henn said of the protests. “[The Park Police] aren’t happy with us being there. And in a way, neither are we.”

This article first appeared on POLITICO Pro at 12:32 p.m. on August 22, 2011.