San Juan Puerto Rico — Four people were killed and five others were in critical condition after a drive-by shooting at a street bar in Puerto Rico, police said Tuesday. Authorities believe Monday night’s shooting is related to drug trafficking.

While Puerto Rico has long served as a transit point for multimillion-dollar drug shipments from South America, drug-related shootings involving multiple victims are considered rare. The shooting raises concerns that this could change.

Police said in a statement that unknown suspects in a moving car opened fire in the northern city of Toa Baja. Two men and two women died and three women and two men were hospitalized. Among those in critical condition was the brother of the former mayor of the coastal city of Cataño, according to police.

Authorities said a 35-year-old suspected drug dealer killed in the shooting appeared to be the target.

No one has been arrested.

This year there have been at least 74 murders on the island of 3.2 million inhabitants, six more than in the same period last year.

Last month, four men and a 16-year-old boy were shot dead on a highway in another drug-related attack in the eastern city of Ceiba.

By Sam