UPDATE x 3: We can report that WWE star Mark Henry is scheduled to undergo an MRI on his hamstring Monday morning prior to RAW. He was also pulled from Sunday night's 9/1 WWE Supershow event in Washington, D.C.. Henry suffered an injury at the 8/31 WWE Supershow in Boston while taking part in a run-in to close the show following Randy Orton vs. Daniel Bryan.

UPDATE x 2: The following was just posted on WWE.com, confirming our earlier reports:

Mark Henry suffered a right hamstring injury at a live event in Boston on Saturday, August 31. This occurred as Henry ran in during the last match of the night. Medical imaging will be obtained to determine the severity of the injury. Stay tuned to WWE.com for any further details.

UPDATE: Live reports from last night's 8/31 WWE Supershow event in Boston noted that WWE star Mark Henry appeared to have injured himself while getting involved with a run-in to close the event following WWE Champion Randy Orton vs. Daniel Bryan. Henry was spotted taking his time getting back up when he hit the ring and looked to be in pain when he backed off. Henry has not commented publicly on Twitter and nor have WWE officials confirmed an injury. WWE has another Supershow tonight in Washington, D.C.

While it's not 100% confirmed, the word among talent is that Henry suffered a hamstring injury of some kind. The injury is not believed to be serious and Henry is expected to work through it.

More as we get it. Stay tuned.

ORIGINAL: Mark Henry appeared to hurt his knee while doing a run-in at the end of last night's Boston, MA WWE house show. Henry apparently hurt himself while hitting the ring and appeared to be in pain as he got up.

WWE sources weren't sure as of right now whether it was just a tweak or an actual injury.

More as the situation develops.