Four Cuban exiles were killed Wednesday in a shootout between Cuban border guards and a U.S. speedboat carrying 10 Cuban exiles. According to the Cuban government, the men on the Florida-registered speedboat opened fire when Cuban forces approached the boat for an inspection off the northeast coast of Cuba. The Cuban guards then fired back, killing four of the men. Six others were injured and are now being held in Cuba. The Cuban government says the men were attempting to carry out “an infiltration with terrorist ends.” Cuban media report the men were carrying weapons, Molotov cocktails, bulletproof jackets and camouflage gear.

On Wednesday, U.S. Secretary of State Marco Rubio said the U.S. would investigate what happened. Rubio was speaking at a gathering of Caribbean leaders, who expressed alarm over the growing humanitarian crisis in Cuba due to a U.S. oil blockade that has cut off the island from desperately needed fuel. On Wednesday, two Mexican navy ships departed from Veracruz with over 1,000 tons of humanitarian aid for Cuba. Russian officials say they’re discussing the possibility of providing fuel to Cuba, and on Wednesday Canada became the latest country to pledge food aid to Cuba. We’ll have more on this story after headlines with Medea Benjamin, co-founder of CodePink, who’s helping organize a humanitarian solidarity mission Cuba next month; she’s just back from the island.