It was a day in the park for about 40 prisoners — handcuffed to each other, a fence and even a children's slide.

Authorities have been holding some crime suspects in a public park in western Bogota's La Granja neighborhood because they say there is no more room at a local detention center.

Prisoners kept at the park, who are suspected of crimes ranging from robbery to drug trafficking, are guarded by groups of six police officers who switch after eight-hour shifts. Thursday's crop of detainees huddled under tarpaulins, slumped beside park play equipment and chatted in groups, their arms linked by handcuffs.

The practice has been going on for more than two months in Colombia's capital. Human rights groups are calling it inhumane and parents are complaining they can't take their kids to the park anymore.

"We worry about safety. The children and my 9-year-old daughter can't come to the park and see this spectacle," said engineer Jaime Rojas, who lives nearby. "There are criminals who have committed all types of crime here."

Hernando Bocanegra Molina, a lawyer for two drug trafficking suspects, called it degrading treatment. Officials can't treat human beings "as if they were animals," he said.

The Attorney General's Office says the problem is a result of overcrowding at all of Bogota's six Immediate Reaction Units, which have been set up by prosecutors to efficiently deal with people arrested as suspects in crimes. If prosecutors deem a case has merit, the prisoner is sent to a regular jail.

The detention center in La Granja has a capacity to hold 70 prisoners but the number of people detained rarely falls below 100 a day.

The director of the La Granja unit declined to comment on the situation.

"Here the problem isn't so much the food or sleeping; the problem is hygiene — where to do our necessities," said one man being held at the park Thursday, declining to give his name for safety reasons.