Complex sentence: After Mendoza witnessed the arrest of his brother via the TV and radio on board the bus which was covered live by the media, he became distressed and ordered the police to release his brother over the radio, or else he would start executing hostages.
Split into simpler sentences: After Mendoza witnessed the arrest of his brother via the TV and radio on board the bus which was covered live by the media, he became agitated. He demanded during a radio interview that the police release his brother, or else he would start executing hostages.