Cannon shots on Friday fired during the 200th anniversary of a national military and immigration monument on the tip of Lower Manhattan startled New Yorkers who were unaware of the celebration.

The event took place for the anniversary of Castle Clinton in Battery Park, the first U.S. immigration station. It was originally built to protect the harbor by keeping the British out during the War of 1812.

“I thought it was a bomb!” said NYC tour guy Amaro Yoro, who was standing outside the park when the shots were fired.

He said he was shaken-up.

“I was very scared. I kept saying ‘What’s going on? What’s going on?’ I saw lots of smoke in the park,” he said.

Yoro said that some people around him were frightened as well but when he looked further out into the park to see what was going on, he realized that many people were relaxed and just going about their business.

“Outside the park we were nervous but inside the park people were calm. I was so confused but then the bomb sound stopped and I figured ‘Ah ok, today, it was just a special day.’

While some like Yoro were extremely frightened others were not and some just didn’t care.

One person sitting right outside the park said he was only a bit startled.

“I was worried but not much because as soon as I heard the sound which sounded like a bomb or a canon I looked up right away to see where it was coming from and felt better when I saw people were so relaxed,” said Terry, who chose not to use his last name.

When Medical Daily asked a pretzel stand owner if he heard the canon shots he said he did but they didn’t affect him.

“I heard but I don’t care,” he said.

Warrant Officer Ken Cullen said that the canon was fired 13 times to represent the 13 original states.