A dispute among members of the Nuclear Regulatory Commission has moved to Capitol Hill, where four NRC commissioners told a House committee that "bullying and intimidation" by the panel's chairman have damaged the commission's effectiveness.

The four commissioners -- two Democrats and two Republicans -- said NRC Chairman Gregory Jaczko, a Democrat, is responsible for an increasingly tense and unsettled work environment at the NRC. The four commissioners sent a letter to the

White House in October expressing "grave concern" about Jaczko's actions.

Commissioner William Ostendorff, a Republican, told a House oversight committee that the letter was not politically motivated, as some lawmakers have said. Ostendorff said the real issue is Jaczko's "bullying and intimidation," which Ostendorff said "should not and cannot be tolerated."

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