The 40-year-old tweets Monday that "there was an explosion by the finish line about 5 minutes after I finished."
He adds: "I'm ok but I'm sure there are many hurt."
Two bombs exploded near the finish line of the Boston Marathon, killing two people and injuring at least 102 others. A senior U.S. intelligence official said two other explosive devices were found near the finish line.
New Kids on the Block is based out of Boston. McIntyre's bandmate Donnie Wahlberg tweeted "please reach out if you hear that (McIntyre) is ok!!!!!" before he heard that his friend was safe.
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