Cuba’s forces fatally shot four people, one of whom was a US citizen, on a Florida-registered speedboat that was trying to enter Cuban waters Wednesday and “infiltrate” the island, authorities said. There were two US citizens among the 10 people aboard the speedboat, a US official told CNN Thursday. The second, who was wounded, was now receiving medical treatment in Cuba, the official said. The shootout comes amid rising tensions between Cuba and the United States, which have both opened investigations into the incident. As more details continue to emerge about the fatal shooting, here’s what we know so far. What happened? Cuban border guard troops approached the boat after it entered the country’s territorial waters in Falcones Cay, Villa Clara province, just over 100 miles from Florida, Cuba’s Interior Ministry said in a statement. A passenger aboard the boat fired at the Cuban patrol vessel, wounding its commander and prompting Cuban forces to return fire, the statement said. ...