Mexico City  - A gang of kidnappers was audacious enough to collect the ransom for an abducted boy at a rally against increasing crimes and kidnappings in Mexico, the boy's mother said Monday.

The 12-year-old boy was abducted Thursday while playing outside the house, his mother Laura Martinez told Mexico's W Radio.

The rally against spiralling crime across the country was held on Saturday and closely monitored by local and federal police.

The kidnappers made an appointment with the victim's parents, asking them to cough up the ransom money during the rally if they wanted their boy back.

Martinez said her husband was told to wait at the Angel of Independence monument at 5 pm local time, from where the rally of 80,000 people would head to Mexico City's central Zocalo square.

The ransom was finally paid about 150 metres away from the monument, and the kidnappers returned the boy to his parents.

An average of 10 people are killed everyday in Mexico and at least three people are kidnapped. (dpa)