A US senator is investigating a union with 600,000 members for working with the Cuban government.

Senator Bill Cassidy asked the International Association of Machinists for information about its ties to Cuba. The union has visited Cuba and supported Cuban policies.

The union did not comment on the investigation.

Senator Cassidy is worried that union members' money is being used to help the Cuban government instead of American workers.

This is part of a larger story about Cuba's influence campaign in the US.

The senator said American workers should not have to pay for advocacy that helps a foreign government, especially one that has hurt US citizens.

In 1996, Cuban fighters killed three US citizens and one US resident in international waters.

A Cuban official spoke at a US union hall and told members how to support Cuba's policies.

US officials are watching the Cuban official for allegedly coordinating influence efforts in the US.

The official told union members how to help Cuba by lobbying and activism.

The US government says Cuba has a secret network in the US.

Senator Cassidy is leading the investigation into the union's ties to Cuba.

A union representative encouraged members to visit Cuba and defend it.

The US State Department reported that Cuba uses labor unions to push for policies that help its government.

Senator Cassidy said the Cuban government uses union members for propaganda.

A union leader said they would continue to defend Cuba's sovereignty.

Senator Cassidy is asking the union many questions about its ties to Cuba.

The senator wants to know if union members have worked with Cuban officials or received payments from Cuba.

The investigation is looking into the union's advocacy efforts related to Cuba policy.

The senator asked for a list of union members who have engaged in activism related to Cuba.

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