AUSTIN (KXAN) – Police identified a man accused of shooting at cars with an assault rifle along an 18-mile stretch of Interstate 35 Saturday morning.

Late Sunday night Rolando Martinez, 25, was charged with aggravated assault with a deadly weapon, a 2nd-degree felony. Four people including a 7-year-old girl were hit. The child remains in critical condition as of Saturday evening.

Austin police say the shooting began about 2 a.m. Saturday and ended around 3:15 a.m. Calls to 911 came in from multiple places along I-35, stretching from south Austin at Stassney Lane up to Wells Branch Parkway.

“We have a lot of crime scenes. We have several people that were injured in this,” said Austin Police Assistant Chief Joseph Chacon on Saturday.

Around 1:52 a.m., police officers were on patrol in north Austin when they heard gunshots nearby. They found nine .223 caliber rounds in the parking lot of the Nocturno Nightclub on North Lamar Boulevard just south of US 183.

At 1:57 a.m., APD dispatch received a call from someone who said his vehicle had been shot at along the I-35 frontage road, a few blocks south of East Braker Lane, according to an arrest warrant affidavit.

At 2:25 a.m. police responded to a call and found three people with gunshot wounds in their car at North Lamar Boulevard and Masterson Pass. A man had a gunshot wound to the back of his head, a woman had a wound on her arm and a young girl also had a head injury. The woman told police they were driving by Diamond Back Trail when they heard a pop noise.

Two minutes later, officers responded to a Valero gas station at I-35 and East Braker Lane where people told them a man driving a black vehicle had pointed a black, AR-style rifle at customers in the parking lot. According to the affidavit, one customer said he was in his car when Martinez approached him.

“[The witness] stated he was scared to exit his vehicle as he was afraid he was going to get shot by [Martinez],” the affidavit stated. “[The witness] stated that [Martinez] had a serious look on his face as he was holding a black assault rifle.”

Police later reviewed surveillance video at the gas station and saw Martinez also point a gun at two men in another vehicle, the affidavit stated.

A man at a gas station on Cameron Road and East 51st Street, which is near I-35, told police around 2:58 a.m. that a man wearing dark clothing and driving a small, black vehicle also threatened him with a gun. Two minutes later, a witness told police that a man pointed a “long black rifle” at him near Cameron Road and 52nd Street, according to the affidavit.

At 3:08 a.m. a woman who was in the same area called 911 and said she was being chased by a man driving a black car. She was driving south on I-35 when the car pulled up next to her and its engine revved. When she got off at the East 51st Street exit he followed her, police said.

When she stopped at the light on Cameron Road, the driver rammed into her. To get a way from the suspect, the woman said she ran the red light but he continued to follow her and that’s when he pointed a rifle at her, according to the affidavit.

The woman’s 4-year-old son was in the car with her. “[The victim] stated that she was in fear for her life and the life of her son, believing they were both at risk of serious bodily injury or death,” the affidavit continued. She immediately sped off to get away from the other driver.

Around 3:10 a.m. a Texas Department of Public Safety trooper found an abandoned vehicle near I-35 and US 290. He saw a man run away from the scene, and later discovered a gun inside the car. According to the affidavit, more than 15 loose shells were scattered inside the car, and their location made it appear that the rifle had been shot out of both the passenger and driver’s side windows. License plate data tracked the car back to Martinez.

Officials arrested Martinez at a home on municipal traffic warrants Saturday. When they questioned him, he told them he had been drinking at the Nocturno Nightclub and didn’t remember much from that night but he did remember waking up in a grassy median near the freeway, according to the affidavit.

KXAN spoke with one of Martinez’s sisters and learned he’s the oldest of six siblings. She described him happy, calm and was shocked to hear the news. The family hasn’t had the chance to speak with him and tearing up, she said she’s “not sure what went wrong that night.”

Martinez’s bond is set at $1 million. According to Travis County Jail records, he has an Immigration and Naturalization Service detainer on him.App users: for an interactive map that shows the shooting timeline, click here