Shortly after President Barack Obama delivered a speech unveiling sweeping reforms to the U.S. immigration system on Thursday, a young woman was arrested for carrying a gun during a demonstration outside of the White House.

Secret Service spokesman Robert Hoback said that April Lenhart, 23, of Mount Morris, Michigan, was arrested around 8:30 p.m. for possession of a firearm while she was demonstrating with dozens of protesters along the north fence of the White House, reports Reuters.

Authorities say they spotted a holstered handgun under her shirt on her hip on Pennsylvania Avenue near the North Lawn, Secret Service spokesman Ed Donovan told CNN.

The people rallying outside the White House were moved off of Pennsylvania Avenue as the arrest was made, Donovan said.

Lenhart was charged with possession of an unregistered firearm and ammunition, and carrying a pistol without a license.

The arrest was made 30 minutes after the president outlined an executive plan of action to overhaul immigration reform. The measures include relaxing deportation laws for 4.7 million undocumented immigrants. In response, Republican leaders promised to put up a fight to block the president's moves.

Lenhart's pastor said that he's "totally baffled" by her arrest.

"All I can say is that at church, she's a wonderful young lady," said Larry Survance, pastor of Eagle's Nest Church on East Mt. Morris Road, according to MLive.com.

According to Survance, Lenhart and her family have attended Eagle's Nest for several years.

"The family pretty much sticks together. They are a close-knit family," he said.

He added that he was shocked by news reports about Lenhart's arrest.

"I'm totally baffled by the whole situation," he said.

Last month, 23-year-old Adesanya managed to jump over the White House fence on the North Lawn and run about 20 feet before he was attacked by two Secret Service K-9 dogs. The Maryland man was then taken into custody by Secret Service officers, reports NBC News.

Adesanya, who was unarmed, was initially treated at a hospital for dog bites before he was brought into custody, said a Secret Service official. The two dogs were also treated by a vet for minor injuries.