Boston Marathon Explosions: Witness tells AP "There are people who are really, really bloody"

(CBS/AP) BOSTON - Witnesses described a bloody scene in the aftermath of two apparent explosions near the Boston Marathon finish line Monday.

PICTURES: Explosions near Boston Marathon finish line

About three hours after the winners crossed the line, there was a loud explosion on the north side of Boylston Street, just before the photo bridge that marks the finish line. Another thunderous explosion could be heard a few seconds later.

Runner Laura McLean of Toronto said she heard two explosions outside the medical tent.

"There are people who are really, really bloody," McLean said. "They were pulling them into the medical tent."

Cherie Falgoust was waiting for her husband, who was running the race.

"I was expecting my husband any minute," she said. "I don't know what this building is ... it just blew. Just a big bomb, a loud boom, and then glass everywhere. Something hit my head. I don't know what it was. I just ducked."

Competitors and race organizers were crying as they fled the chaos. Bloody spectators were being carried to the medical tent that had been set up to care for fatigued runners.

"There are a lot of people down," said one man, whose bib No. 17528 identified him as Frank Deruyter. He was not injured, but marathon workers were carrying one woman, who did not appear to be a runner, to the medical area as blood gushed from her leg. A Boston police officer was wheeled from the course with a leg injury that was bleeding.