The jail in the port city of Sorong was targeted in violence sparked by claims of racist abuse and physical mistreatment of Papuans studying elsewhere in Indonesia.

Protesters had attacked the jail among other buildings, said Ade Kusmanto, a spokesman for the director-general of correctional facilities at the Law and Human Rights ministry.

"After burning the regional government's office facilities, (protesters) headed to the prison and threw rocks, provoking inmates," said Kusmanto, adding that a prison warden had been injured in the unrest.

The official said 258 inmates had escaped, from among 547 held in the jail, but added that some had since been recaptured, without elaborating.

Thousands of people took the streets of the cities of Sorong, Manokwari and Jayapura in Monday's protests, blocking roads, damaging an airport and torching a town hall.

The protests were triggered by the detention of Papuan students in the East Java city of Surabaya following accusations that they had disrespected the Indonesian flag in front of a dormitory during celebrations of Independence Day on Saturday.

Police fired tear gas into the dormitory before arresting 43 students, according to an activist, who said the students had been called "monkeys" during the operation.

Papuans were angry because of "the extremely racist words used by East Java people, the police and military," Papua Governor Lukas Enembe said on Monday.

A separatist movement has simmered for decades in the resource-rich area of Papua, where there have been frequent complaints of rights abuses by security forces.

REUTERS