允许美军入境？墨西哥参议院爆发肢体冲突，场面一度失控

Group 1 - The core incident involved a physical altercation between PRI leader Moreno and Morena party member Noronia during a Senate meeting in Mexico, highlighting tensions within the political landscape [1][3] - The meeting's agenda included a controversial topic regarding the potential entry of foreign military forces into Mexico, which has sparked accusations of supporting U.S. military intervention from the ruling party against opposition parties [3] - Moreno accused the ruling party of deliberately altering the agenda to suppress opposition voices, leading to the conflict, while Noronia claimed the opposition provoked the situation [3] Group 2 - The altercation is noted as rare in the Mexican Congress, although not unprecedented, with a similar incident occurring in 2006 during a disputed presidential election [3]