Madrid, Jan 5 - Police are trying to trace the origin of some 100 kg of cocaine hidden in boxes of bananas that were about to go on sale at several supermarkets in Madrid and two other cities in Spain.

The investigation started when an employee at one of the supermarkets emptied out a box of bananas and found a "block" of cocaine inside, police spokesmen told EFE over the weekend.

Police officers found several other "bricks" of a substance, which tests confirmed was cocaine, in various boxes of bananas that had arrived at the supermarket from the Mercamadrid central food market.

Cocaine was found at other Lidl supermarkets in Madrid and the western cities of Caceres and Plasencia.

The cocaine was carefully wrapped and did not get mixed up with the bananas.

Investigators have gone to all the supermarkets, seizing a total of about 100 kg of cocaine, police said.

Police are trying to determine how the cocaine arrived at the supermarkets belonging to Lidl, which has stores in several European countries, where it came from and what the ultimate destination was.

Investigators have determined that the Lidl chain had nothing to do with the cocaine, receiving the illegal drugs due to an error by the gang that smuggled it into the country.

The drug traffickers likely did not have enough time to get the cocaine out of the boxes before the bananas were distributed to supermarkets, police said. (IANS)