Reports says about a dozen inmates at an overcrowded Brazilian prison have tunnelled to freedom, and another group made a failed attempt to scale the wall.
A department spokesman said the high-security prisoners broke out of the infamous Pedrinhas prison in the northeastern city of Sao Luis de Maranhao, site of numerous attempts to escape conditions renowned as hellish.
Brazilian television reported from the site that at least 10 prisoners were believed to have escaped through the tunnel, but authorities could not confirm the figure.
The G1 web news portal showed images from the tunnel exit and a pile of earth which appeared to have escaped the authorities' notice ahead of the inmates' dawn exit.
It was unclear how many prisoners had escaped.
"There was no visit or inspection on Sunday, Monday or Tuesday, allowing them to get on with digging out their tunnel," said Sebastiao Uchia, Maranhao secretary of state for justice told G1 before handing in his own resignation.
How come there were no checks for three days? Someone has to be held to account
Tunnelling is an age-old means of jailbreaking, and in Pedrinhas around 20 prisoners took advantage of the commotion caused by the first escape to break out of their cells and converge on the front gate.
There, some tried to jump a wall topped with barbed wire which they attacked with cutters before elite police nabbed them, Globo News reported.
Escape attempts have been on the rise in recent weeks in Brazil, which has 274 people in prison per 100,000 residents, according to the International Centre of Penitentiary Studies, causing facilities to burst at the seams.
Last week, 36 prisoners escaped from Pedrinhas after a stealing a dumper truck and using it to breach the rear wall of the facility. Just one was recaptured.
This month alone has now seen three escapes from the same facility.
On Monday, police arrested a prison director accused of taking bribes to look the other way.
Pedrinhas, with a capacity of 1,700 prisoners but currently crammed with 2,500, has been the scene of repeated riots and killings of inmates.
At least 15 have been killed this year, following on from 60 last year - three were decapitated and grisly footage was posted online.
Five prisoners were killed and 25 wounded in a riot at a prison in Cascavel in the southern state of Parana, where inmates took two guards hostage.