EVERETT — Snohomish County deputy prosecutor Adam Cornell and his wife were sitting in a Boston hotel Monday afternoon, listening to the wailing of sirens as emergency crews continued to tend to the dozens of people injured in two explosions at the Boston Marathon.

Cornell had crossed the finish line about an hour before the blasts.

His wife, who was there to cheer him on, had walked by one of the sites about 20 minutes before the deadly explosions.

The couple was in their hotel room about a block away when the chaos erupted outside.

“It could have been my wife or me,” Cornell said. “It’s just, just unfathomable.”

At least 35 people from Snohomish and Island counties were listed as having participated in the marathon.

Cornell said he was resting after the race when he first heard sirens. His wife heard a loud boom from their room.

They turned on the news. That’s when they learned what had happened just about a block away.

Cornell said he initially couldn’t help but think of the 9/11 terrorists attacks on the World Trade Center.

He and his wife also realized how close they had come to being hurt.

“Other people were not so lucky,” Cornell said.

The couple has been letting friends and family know that they are OK through phone calls and Facebook posts.

Their hotel was in lockdown. They were glued to the television. Outside their window they could see ambulances lined up for at least two blocks. The sirens continued to scream outside, Cornell told The Herald.

This was the first time Cornell ran the famous Boston race.

“My memory of my first Boston Marathon will not be about finishing the race but about the innocent people who were harmed for some unknown reason,” he said.

Diana Hefley: 425-339-3463; hefley@heraldnet.com.