A daring prison breakout in Mexico captured on CCTV - dressed as policemen, these gang members storm a prison and set dozens of inmates free.

Breakouts like these, as well as bloody riots, are becoming increasingly common in a country whose penal system is being stretched to the limits.

Forty-four prisoners were brutally killed on Sunday after a mass jailbreak by one gang at a prison in Mexico City.

Meanwhile, twenty-nine prison officials - including the prison chief - were arrested, accused of aiding the gang.

As authorities try and crack down on spiralling drug related violence, fuelled by deadly rivalries between gangs, Mexico's jails are running out of space.

Relatives say the conditions are unbearable.

(SOUNDBITE) (Spanish) RELATIVE OF INMATE, MONTSERRAT SANDOVAL SAYING:

"The food is terrible. They give them stale bread with water and guards treat them badly. If they are not present at roll call they are punished. They treat them very bad."

UN Human rights commissioner David Hernandez says the government needs to address fundamental problems.

(SOUNDBITE) (Spanish) UN HUMAN RIGHTS COMMISSION IN MEXICO, JAVIER HERNANDEZ SAYING:

"We have the problem of overpopulation which leads to self-government. The prisoners are territorial and authorities do not rule. It's the drug lords and cartels who rule. This reorders and perpetuates the business of criminal organisations."

But with the country's bloody drug war showing no signs of abating, the pressure on Mexico's crumbling prison system is unlikely to ease anytime soon.

Sunita Rappai, Reuters