Three police officers were shot and killed Monday allegedly by a fellow officer Monday at a police station in Ponce, Puerto Rico, authorities in the US territory said, according to dpa. The suspect, who reportedly suffered emotional problems, shot and killed a police commander and two other officers at the police headquarters in the a coastal city, about 100 kilometres south-west of the capital, San Juan. The alleged gunman was taken into custody. "There are no words to describe this tragedy where three colleagues have lost their lives. Our condolences for the families," Puerto Rico Police Deputy Superintendent Colonel Juan Rodriguez Davila said on the Twitter page of Puerto Rico's police force. Authorities gave no motive. The newspaper El Nuevo Dia reported that shortly before the shooting there had been a dispute within the bureau. Sources told the newspaper that the suspect had exhibited behavioural problems for several years.