George Schemel had passed the finish line Monday at the 2013 Boston Marathon about five minutes before a pair of explosions echoed through the city streets.

“It sounded like two cannons going off,” Schemel said, talking on his cell phone from his Boston hotel room late Monday afternoon. “We all looked and just saw all this smoke.”

“It was incredible. It was crazy,” he said. “I’m very lucky. I missed it by only five minutes.”

The 52-year-old Colorado Springs man had just finished his third Boston Marathon in as many years. He said each time, the annual event was “a joy.” He was among about 45 runners from the Pikes Peak region.

“Everybody is super happy to be here and then to have this happen,” the obviously distraught man said before pausing.

Schemel said Boston’s subway system was immediately shut down and police cleared the street to let emergency vehicles through. Officials did not let the runners go back toward the finish line where the explosions were later determined to have killed at least two people and injured dozens more.

A friendly stranger stopped Schemel, who was in Boston by himself, and asked him if he needed a ride. Schemel accepted and went back to his hotel where he tuned in to new broadcasts, struggling to find any new information about the tragedy.

“People around the hotel are like me,” he said. “Everybody’s more curious than anything.”

Schemel said Boston authorities were on high alert in case other explosives had been planted in the city.

The Boston Marathon website listed 521 runners from Colorado, including 39 from Colorado Springs, two from Manitou Springs, three from Monument and one from Canon City.

Steve Bremner, who lives in Manitou Springs and is president of the Incline Friends organization, also ran the race Monday.

Bremner said he was too far away from where the explosions occurred to see or hear anything, but noted that a friend and fellow runner was within a block or two of where the tragedy happened. The friend’s experience was similar to Schemel’s.

“He said he heard two loud explosions and saw a bunch of white smoke,” Bremner said.

The Manitou Springs runner, who was on his way to the airport at about 1:30 p.m. Monday, said he saw “tons and tons of ambulances and fire trucks going to the scene.”