Cuban authorities say they have intercepted more than a dozen speedboats arriving from the United States this year - including two shooting incidents and at least one death.
They say US authorities have handed over a suspect in the shooting of a Cuban coast guard officer.
The Interior Ministry statement read over state television on Monday night comes amid a sharp increase in migration from Cuba to the United States, both by sea and via Mexico, at a time of economic hardships aggravated by the pandemic and by tightened US sanctions.
The ministry said its coast guard units had intercepted 13 speedboats from the US entering Cuban waters this year, with 23 crew members.
It was not clear how many of the boats might have reached shore or how many of those aboard were arrested.
It mentioned at least some arrests but also at least one case in which a boat escaped.
"Recently situations of greater violence and aggressiveness have occurred, with the use of firearms" against Cuban coast guard units, the ministry said.
It said in one incident, agents intercepted a Dakota speedboat with a Florida registration number 3 nautical miles north of Bahia Honda, on the coast west of Havana, and were fired upon.
The ministry said troops returned fire, killing one of those aboard the speedboat.
That boat was detained and the ministry said it found drugs and evidence of firearms use aboard.
It said US authorities were informed about the identities of those arrested and the man who died.
In another case on June 18, it said people aboard a speedboat near Cayo Fragoso off the central Cuban province of Villa Clara opened fire with an automatic weapon at close range, wounding one Cuban officer, and then raced off northward as Cubans took away the wounded man for treatment.
It said Cuban officials notified the US Coast Guard, asking for help to detain the attackers.
On Monday, one Cuban citizen "implicated in the aggression" had been returned to the island, it said, under an agreement by which the US returns Cubans attempting to immigrate illegally.
"In parallel," it said, 30 people who were trying to leave the island were found by Interior Ministry agents and were being investigated.
In a separate statement on Monday, the Interior Ministry said its coast guard troops found six of 15 people who had set out in makeshift board that sank last week.
It said there was no word on what happened to the other nine.
The 15 apparently had set out from the area of Playa Jibacoa along the coast east of Havana on June 20.
The US Coast Guard said that so far this fiscal year it has intercepted 2900 Cuban migrants at sea, up from just 838 in the previous fiscal year and 49 in 2020.
Australian Associated Press
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