Madrid city hall has apologized to parents for exposing their children to a violent puppet show, but says authorities' decision to jail the puppeteers for allegedly praising terrorism was disproportionate.

The two puppeteers were detained without possibility of bail Friday for using a sign saying, "Long Live Alka ETA," in a word-play reference to Spain's armed Basque group ETA and al-Qaida during the show commissioned by the city.

The satirical theater piece also featured the hanging of a judge's effigy, the stabbing of a nun with a crucifix and police beatings, leading parents attending with children to complain.

Madrid Mayor Manuela Carmena said Monday the show's content was inappropriate for children but argued the jailing of the puppeteers was incomprehensible.

Praising terrorism has been a crime in Spain since 1995.