Rep. John Larson (D-CT) said he suffered a “complex partial seizure” Monday that caused his speech to stop abruptly during his speech on the House floor. Larson, 76, was in the middle of a floor speech when he stopped speaking mid-sentence.

Connecticut U.S. Rep. John Larson, who inexplicably stopped speaking during a speech Monday on the House of Representatives floor, says he suffered a complex partial seizure.

Rep. John Larson (D-Conn.) said Tuesday that a "complex partial seizure" was what caused him to seize up during a House floor speech the previous day. Why it matters: The 76-year-old's office had initially said the incident — which quickly went viral on social media — was likely caused by an "adverse reaction to a new medication.