Michael Watson, 18, was arrested on suspicion of armed robbery and attempted homicide.
Michael Watson, 18, was arrested on suspicion of armed robbery and attempted homicide.

LIVERMORE -- A man and four teens were arrested on suspicion of robbery and attempted murder after police say they nearly beat a man to death under the Stanley Boulevard Bridge earlier this month, but prosecutors said there was only enough evidence to charge one person with attempted murder.

Officers responded about 3 a.m. on June 14 to the jogging path under the bridge at the corner of Murrieta Boulevard and Stanley Boulevard after receiving several calls for an in-progress battery.

Witnesses who dialed 911 reported seeing a group of males beating a man with sticks and pipes, said Officer Steve Goard.

Responding officers found the victim on the ground suffering severe upper body and facial injuries, Goard said. He was transported to a hospital where he was admitted to the intensive care unit with injuries not considered life-threatening and later underwent several surgeries.

On June 19, police acting on citizen tips arrested four juvenile males, ages 16 and 17 years, and Michael Watson, 18. All five suspects are from Livermore, and were arrested on suspicion of robbery in connection to a strong-arm robbery that took place about seven hours before the beating, at 8:15 p.m. June 13 in the 2100 block of Park Street.

Watson was also arrested on suspicion of attempted murder, Goard said.

On Tuesday, detectives presented the case to the Alameda County District Attorney's Office and Juvenile Division for charging, but citing a lack of evidence, prosecutors charged only one juvenile with attempted murder and robbery, and one other with robbery. Both remained in custody at Juvenile Hall on Thursday.

Anyone with information about the case is asked to call police at 925-371-4755.

Contact Natalie Neysa Alund at 510-293-2469. Follow her at Twitter.com/nataliealund.