(CBS) CHATTANOOGA, Tenn. – A Chattanooga school bus driver has been indicted on six counts of vehicular homicide in a crash last November that killed a half-dozen children.

Media reported Wednesday that 24-year-old Johnthony Walker also was charged by a grand jury with four counts of reckless aggravated assault, one count of reckless endangerment, one count of reckless driving and one count of use of a portable electronic device by a school bus driver.

Arraignment is scheduled March 24 before Criminal Court Judge Don Poole.

Authorities have said Walker was speeding Nov. 21 when the bus swerved into a tree with 37 elementary school students aboard, killing six children and injuring several more.

Jailed since the wreck, Walker is facing about a dozen lawsuits arising from the crash.