DALLAS (AP) - A co-conspirator of a bank robber serving life in prison for killing a North Texas armored car guard has pleaded guilty in a string of 2009 holdups.

Prosecutors in Dallas say 50-year-old Jesus Sandoval on Thursday pleaded guilty to conspiracy to commit bank robbery, to two counts of using, carrying, and brandishing a firearm and to possessing a firearm to further a violent crime.

Sandoval faces up to life in prison when he's sentenced in May for three robberies with 28-year-old Enrique Lopez. Both were arrested on Oct. 3, 2009, in suburban Dallas.

Lopez last year pleaded guilty to five robberies and to killing Brinks Security guard Cresencio Borquez during a September 2009 holdup in Dallas. He was sentenced to two consecutive life terms plus 85 years in prison.

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