HOUSTON -- The driver accused of fatally running over a police officer and injuring another told his side of the story to KPRC Local 2 on Wednesday.

When Hung Truong came out to speak with KPRC Local 2's Elizabeth Scarborough in the visitor's area of the Baker Street Jail, he was handcuffed and wearing the same orange jumpsuit he had on in court. He also had a familiar look on his face -- a smile.

He laughed throughout the interview.

Scarborough asked how he was doing since his incarceration.

"I'm OK," he said.

He spoke softly and in short sentences.

He said since the accident he'd been "worried and scared" and "thinking about it."

He has been charged with manslaughter in connection with the death of 47-year-old Officer Gary Gryder, a 25-year Houston Police Department veteran. He is also accused of seriously injuring Officer Joe Pyland, who is now recovering at home.

Police said Truong's vehicle slammed into barricades at a construction site on the Katy Freeway feeder road at Highway 6 early Sunday and kept going, hitting the two officers working an extra job there.

Truong said he had just finished working at Sercel Industries, where he said he had "worked with cables for last month and a half." He said it was a 12-hour shift from 5 p.m. Saturday to 5 a.m. Sunday.

He said several times that he was "tired."

He said he was driving home, when he "fell asleep," "ran a red light," and was "going about 60 mph." He said that was when he hit the barricade.

As he was placed in handcuffs, he appeared to laugh. Scarborough asked why.

"I don't know what to say," he said. "That's how I am."

He insisted he was not on any drugs or alcohol and preliminary tests showed nothing in his system.

A source told KPRC Local 2 that Truong has said he heard voices in his head before the crash. When he spoke with Scarborough, Truong said he has no mental defect.

The court has ordered a 21-day mental evaluation.

"I don't think I need it," Truong said.

KPRC Local 2 legal analyst Brian Wice said the evaluation could be very useful for Truong's lawyer because it will help determine an important thing.

"If their client is competent to stand trial or if he was sane at time of the offense," said Brian Wice.

Gryder's funeral is scheduled for 10:30 a.m. Thursday at the Champion Forest Baptist Church, 15555 Stuebner-Airline Road.