Updated

Distraught families are clamoring for information about detained relatives following a fire that Venezuela's chief prosecutor says killed 68 people when it swept through the cells of the state police station.

Angry relatives fought with police outside the facility Wednesday after being unable to get any information on casualties from Wednesday's fire, which townspeople said erupted after a disturbance involving detainees. Officers used tear gas to disperse the crowd, and local officials would confirm only that there were fatalities.

Late Wednesday, Attorney General Tarek William Saab said on his official Twitter account that 68 people were dead and nearly all of them were prisoners. He said the dead included two women who were staying overnight at the station, but he didn't provide any further details.

Saab said four prosecutors had been named to determine what happened at the state police headquarters in Valencia, a town in Carabobo state about 100 miles (160 kilometers) west of Caracas.

It was one of the worst jail disasters in Venezuela, where human rights groups complain about poor conditions in prisons and jails. A fire at a prison in the western state of Zulia killed more than 100 inmates in 1994.

With tears streaking cheeks, people waiting outside the station Wednesday said dozens of detainees had been kept in squalid conditions and they feared the worst for their loved ones.

Some people buried their hands in their faces. Others had to be supported by friends and family as they collapsed in despair. Some wept quietly and clutched their hands in prayer.

"I don't know if my son is dead or alive!" cried Aida Parra, who said she last saw her son the previous day, when she took food to him. "They haven't told me anything."

Nearby, National Guard troops wearing flak jackets and carrying rifles slung across their backs walked in and out of the station. Fire trucks and ambulances stood outside. Unused stretchers leaned against a wall.

A Window to Freedom, a nonprofit group that monitors conditions at Venezuela's jails and prisons, said preliminary but unconfirmed information indicated the riot began when an armed detainee shot an officer in the leg. Shortly after that a fire broke out, with flames growing quickly as the blaze spread to mattresses in the cells, it said. Rescuers apparently had to break a hole through a wall to free some of the prisoners inside.

Photos shared by the group showed prisoners being taken out on stretchers, their limbs frozen in awkward positions as skin peeled off.

Carlos Nieto Palma, director of A Window to Freedom, said officials should be held accountable for failing to address the poor conditions in police station jails. The group said overcrowding has become common throughout Venezuela, with detainees being kept long past customary brief holding periods before being let go or sent to larger jails to await trial.

"It's grave and alarming," Nieto Palma said. "What happened today in Carabobo is a sign of that."

Opposition lawmaker Juan Miguel Matheus demanded that the pro-government leader of Carabobo state inform relatives about what happened.

"The desperation of relatives should not be played with," he said.

Clashes between prisoners and guards are not uncommon in Venezuela. Inmates are frequently able to obtain weapons and drugs with the help of corrupt guards and heavily armed groups control cellblock fiefdoms.