Three suspected leaders of a failed coup against Bolivian President Luis Arce were Friday remanded in custody for six months, the country’s top prosecutor said.

Former army chief Juan Jose Zuniga, former head of navy Juan Arnez, and Alejandro Irahola, former head of the army’s mechanized brigade, will be held in a high-security prison not far from the capital, La Paz.

A total of 21 active, retired, and civilian military personnel were arrested in connection with Wednesday’s attempted coup, in which troops and tanks were deployed in the heart of the capital, where they tried to break down a door of the presidential palace.

Zuniga said his goal was to “restructure democracy” in Bolivia. He was soon captured and the troops pulled back.