Ryan Karr, the Santa Rosa man involved in a fiery Highway 101 crash in January that killed five people, was arrested Thursday and booked on five felony counts of vehicular manslaughter, a CHP spokeswoman said.

Karr, 26, also was booked on five misdemeanor counts of manslaughter and one misdemeanor drug charge, Officer Barbara Upham said.

Karr?s arrest at his Rincon Valley home followed a 10-month investigation into the Jan. 17 crash near Windsor.

Upham declined further comment, saying the Sonoma County district attorney was now handling the case. The CHPturned over its investigation in November.

Calls to the District Attorney?s Office weren?t immediately returned. Karr?s attorney, Andy Martinez, also did not immediately return calls.

The CHP said Karr was driving a Mitsubishi coupe in rush-hour traffic on northbound Highway 101 when he rear-ended a Honda Civic carrying six passengers.

The Honda burst into flames, trapping five occupants. Witnesses rescued a 5-year-old boy, who was hospitalized for months with severe burns.

Karr reportedly told investigators he was not paying attention when the crash happened.

The lone survivor was Christian Flores Carlos of Windsor.

His mother, Edith Carlos Medina, 23, was driving and suffered fatal injuries.

So did his grandmother Maria Lopez Camacho, 54; brother, Fernando Flores Carlos, 7; and aunts Almadelia Mendera-Basurto, 16, and Carmina Solorio, 23.

Christian?s aunt Francisca Jimenez welcomed the news of Karr?s arrest.

?I just don?t know why he wasn?t arrested sooner,? she said.

Jimenez said Christian?s physical condition continues to improve. She said he attends school in a wheelchair and can walk with the help of others using a prosthetic leg.

But Jimenez said the boy continues to suffer emotionally from the loss of his mother, older brother, grandmother and aunts.

?I always thought that eventually (Karr) would have to go to jail,? Jimenez said. ?It wasn?t just a dog that he killed, it was a whole family.?