Security forces have retaken control of an overcrowded prison in western Indonesia following a night-long riot, and have captured most of the estimated 30 convicts who escaped, authorities say.
The riot erupted on Sunday afternoon at the Labuhan Ruku jail, which was built for around 300 prisoners but houses more than 850, most of them drug traffickers.
Local police chief Lieutenant Colonel Japerson Sinaga said the rioting began when a warden was beaten by inmates who had just been transferred to the facility from other prisons.
Inmates torched the prison in North Sumatra province and at least 30 prisoners overpowered security guards and scaled a 2-metre wall.
A warden and a male inmate were hospitalised with injuries, and 23 inmates have been captured, including four who turned themselves in to authorities, Sinaga said.
He said the exact number of missing inmates is unclear because the fire destroyed prison records.
"We call on other prisoners on the loose to surrender," Sinaga said. "We will not hesitate to take firm action to force them to obey the law."
Prison officials said the inmates who started the riot were angry that they had been transferred to an overcrowded prison far from their families.
Security forces moved 25 female inmates early Monday to another prison in the neighbouring district of Tanjung Balai. A pregnant prisoner was taken to the hospital.
Transfers were planned for other inmates to 13 jails on Sumatra island because more than 75 per cent of the facility was damaged by the fire, said prison chief Sutopo Brutu.
It was the second jailbreak in the province and the third in Indonesia this year.
In July, about 240 prisoners, including several convicted terrorists, escaped following a deadly riot at a facility in Medan, the country's third-largest city. About 90 of the convicts remain at large.
Days after the riot in Medan, 12 inmates overpowered guards and escaped from another crowded prison in Batam, off Sumatra island.