Madrid- Spain's highest court Thursday overturned the guilty verdicts of four of the 21 persons convicted of carrying out the Madrid train bombings that left 191 dead four years ago.

The court acquitted two Syrians, a Moroccan and a Spaniard, who were sentenced to between 5 and 12 years in October 2007 for smuggling explosives and membership of a terrorist organization.

Another Spaniard acquitted at the orginal trial was convicted at the latest hearing and jailed for four years.

The court also confirmed the acquittal of Rabei Osman el-Sayed Ahmed, known as Mohammed the Egyptian, who was suspected of masterminding the March 11, 2004 attacks on four commuter trains.

The 36-year-old was acquitted of belonging to a terrorist organization because he had already been sentenced for the same crime in Italy.

At the original trial, 17 Arabs and four Spaniards were found guilty and sentenced to prison terms ranging from three years to 40,000 years. Seven of the accused were acquitted. (dpa)