Motörhead have been forced to cancel a pair of shows on their North American tour.

The latest cancellations, which affect scheduled performances in Dallas tonight and Houston tomorrow, come after frontman Lemmy Kilmister experienced health issues during recent dates. The group's Salt Lake City stop was cut short when he experienced shortness of breath, leading to the cancellation of their Denver show; earlier this week in Austin, Lemmy's ill health again forced the band to leave the stage.

"As you might have heard, Motörhead again had to abbreviate a performance due to Lemmy not feeling well," explained the band in a statement released after the Austin concert. "This is a DIRECT follow-on from the altitude issues in Colorado, and clearly, Lemmy tried to get back at it too quickly. For this reason, Motörhead will not play in San Antonio tonight, but the show will still go on with Saxon headlining. Lemmy will resume duties the moment he is PROPERLY rested and firing on all cylinders again. The legendary Motörheadbanger patience is much appreciated, and the band send their deepest thanks. More details will be released soon."

Lemmy's current health woes come as the band is promoting its new Bad Magic LP, and follow a period in which he seemed to be on the rebound after a rough patch in which he suffered a hematoma and battled heart problems.

Motörhead's tour is currently scheduled to pick up again Sept. 8 in St. Louis, but whether the band is actually able to fulfill that date obviously remains to be seen. Here's hoping Lemmy is feeling well enough to play again soon.

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