SAN JUAN, Puerto Rico (AP) — Gunmen opened fire at a birthday party in northern Puerto Rico and killed three people including a 4-year-old boy, police said Tuesday.

The shooting injured two other children, ages 9 and 10, in the attack Monday night at a public housing complex in the U.S. territory’s coastal town of Cataño, police said in a statement.

Police said two men were killed at the party and that the 4-year-old boy died at a hospital on Tuesday.

Officials said the boy was not related to the men, adding that they believe the shooting was tied to drug trafficking.

No one has been arrested.

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