Ten alleged gang members were convicted Thursday in the killings of 12 women, some of the hundreds who have been found slain in this border city in recent years.

Four bus drivers, all thought to be loyal to a criminal gang known as "Los Toltecas (search)," were sentenced to between 40 and 113 years in prison for premeditated homicide, aggravated rape and criminal association in the slayings of six Ciudad Juarez (search) women.

In a verdict delivered by a different judge, six members of another gang, "Los Rebeldes (search)," received between 24 and 40 years in prison for similar convictions in the deaths of six other women, said Rene Medrano, a spokesman for the state attorney general's office in Chihuahua, which includes Juarez.

The Los Toltecas members were arrested in 1999, after the reputed leader of their group, Jesus Manuel Guardado, alias "El Tolteca," was identified by a 14-year-old girl as the man who sexually assaulted and tried to kill her.

Guardado, whose nickname comes from inhabitants of an ancient civilization that predates the Spanish conquest, received 113 years in prison, while the other four were sentenced to 40 years. Under Mexican law 40 years is the longest any inmate can be held behind bars.

One other alleged member of the group was acquitted and released, Medrano said.

According to government tallies, at least 300 women have been killed in this city across from El Paso, Texas, since 1993. Human rights activists say the number is much higher.

Many of the victims have been young women who were sexually abused, strangled, and dumped in the desert outside Juarez.

Few cases have been solved, and only two men had been convicted for nine of the slayings. The first person found guilty was Abdel Latif Sharif, a U.S. resident and Egyptian-born chemist, who was arrested in 1996 and sentenced to 20 years in prison.

Women continued to turn up dead in and around Juarez after Sharif's detention, and police alleged he paid members of Los Rebeldes to continue raping and killing other women to deflect suspicion.

In October, a bus driver, Victor Garcia Uribe, was convicted of killing eight women whose bodies were found in a vacant lot in Ciudad Juarez in 2001. He was sentenced to 50 years in prison.

The six alleged Los Rebeldes members sentenced Thursday were among 11 suspected gang members detained in 1996 on suspicion of ties to Sharif. The judge found there was enough evidence to convict them in six killings committed before 1996.