The school bus driver accused of taking 13 children on an unauthorized trip to Maryland with a loaded gun stowed behind his seat Thursday had passed extensive background checks, school officials said.

Otto Nuss, 63, had passed both criminal and child-abuse background checks, according to Superintendent Jeffrey Zackon of the Oley Valley School District. Officials said he would have also needed a commercial driver's license to be hired.

"We have to re-examine the whole process. Obviously, I'm concerned," Zackon said.

Nuss allegedly picked up the children and drove them to Landover Hills, Md., more than 100 miles from the private school in eastern Pennsylvania where he was supposed to go. Nuss gave up to an off-duty police officer and no one was hurt.

Nuss faces federal kidnapping charges.

Nuss worked for Quigley Bus Service, which has a contract with the school district to transport students. Bus company officials said they were happy no one was injured, but declined further comment.

Friends and neighbors described Nuss as mild-mannered.

"It's totally out of character. He's a very good neighbor, a kind and gentle man. He's even fed our dog for us when we've been gone," said Lindy Postell, who lives across the street from Nuss.

She called Nuss a conscientious driver who put chains on the tires of the bus a few days ago because he was worried about snow on the back roads.

"(There were) no hints of anything like this in any way, shape or form. It was completely out of the blue," said Robert Becker, administrator of the Berks Christian School, where the bus was supposed to go.

Nuss had recently borrowed a shovel from a secretary to clear a path for children to walk to the bus, Becker said.

Nuss had not driven a school bus before this year, according to Cindy Calcagno, assistant transportation director for the school district.

"He loved the kids," said Calcagno, who had driven the route until this school year.

Nuss lived alone in the rural community of Colebrookdale, in a newer split-level house on a hill overlooking a pond. He kept the school bus in the driveway, Postell said.

Police Chief Darius Puff said Nuss had never caused any problems. His only meeting with Nuss involved a car accident more than a decade ago, Puff said.

Nuss graduated from Boyertown Area High School in 1957. According to the yearbook, Otto Lawrence "Sonny" Nuss was an avid hunter who hoped to become a farmer. WCAU-TV said he worked for 30 years at Mrs. Smith's Pies in Pottstown, which is now closed.

Terry Van Lear, president of the Pennsylvania School Bus Association, said 80 percent of all school buses in Pennsylvania are operated by private contractors.

"In Pennsylvania, we got a pretty good set of standards that protect our children. However, I thought we had a good system in our skies until Sept. 11," Van Lear said.