LA PAZ, March 14 (Xinhua) -- At least six inmates were killed and more than 20 people injured on Wednesday in an armed clash between inmates and police in Bolivia, said authorities.

The violence at the Palmasola Prison in Bolivia's eastern city of Santa Cruz erupted after an inspection turned up drugs, weapons, alcohol and other items the inmates are banned from possessing, Deputy Interior Minister Jose Luis Quiroga told a press conference.

"We took control of the prison after the inmates resisted the requisition of the banned items," said Quiroga.

"We are going to impose discipline to prevent powerful gangs from operating inside this prison," he added.

According to the police report, more than 2,300 heavily armed officers entered the facility at dawn to carry out the inspection, with helicopters providing support from the air. A five-block area around the prison was cordoned off.

After police uncovered some of the items, inmates fired on the officers and a firefight ensued.

According to Quiroga, six people who resisted the police incursion were killed.

Among the injured were 18 inmates and six officers, said the chief of police, Gen. Faustino Mendoza.

"It was a successful operation. Today we can tell the people that we have taken control of the prison. We have identified several (gang) leaders and are going to relocate them," said Mendoza.