The Montgomery County Sheriff's Office said the original crash happened at I-45 North near Lake Woodlands at 2:40 a.m. on Sunday.
Investigators identified one of the drivers in that initial crash as 34-year-old Ashton Jammer. According to officials, he was charged with driving while intoxicated and will be taken to the Montgomery County Jail.
Less than 30 minutes after the first crash, authorities received a call reporting that deputies trying to direct traffic at the crash scene were struck by a different vehicle.
The driver of that vehicle was transported to a local hospital.
When ABC13 arrived at the scene Sunday morning, at least five vehicles, including a heavily damaged deputy car, remained at the crash site.
Both directions of the North Freeway are experiencing traffic disruptions, with northbound traffic being diverted at Rayford Road and at least one southbound lane blocked by law enforcement vehicles as the investigation continues.
The deputy killed was identified as 24-year-old Erika Serrato. Investigators said she was hit by a heavy commercial vehicle and was taken to the hospital, where she later died.
According to Sheriff Doolittle, Serrato worked for the Montgomery County Sheriff's Office for six years, first as a detention officer at the jail, and started patrolling six months ago.
The injured deputy, identified as John Hernandez, was hurt by debris from the crash. Deputies said he is expected to be OK.
This is a developing story. Eyewitness News is continuing to gather facts.
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