The 5-year-old kindergarten student who was fatally hit by a school bus in Standish in December had become stuck in the bus doors while trying to get on board, according to a preliminary report released Thursday.

After the crash last month, police identified the student as Simon Gonzalez. His death came just three weeks after another student, 12-year-old Brayden Callahan, was hit and killed by a school bus in Rockland.

Simon attended Edna Libby Elementary School in the Bonny Eagle school district. Friends and family remembered him as a “special boy” who loved his family and the color yellow.

The National Transportation Safety Board’s initial report about the crash states that he was killed on the morning of Dec. 16 after trying to get on a school bus at a stop along Route 35 in Standish.

He approached the bus from the right rear, but as he attempted to board, the doors closed on his arm. When the bus began to move, he was dragged almost 300 feet before he fell into the road and was run over by the bus, according to the report.

The safety board’s final report may take more than a year to be completed, said Sarah Taylor Sulick, a spokesperson for the agency. That report will be more detailed and include analysis and recommendations from the safety board, she said.

The bus driver, 64-year-old Lori Ann Merrifield, has not been charged in connection with the crash, according to the Cumberland County Sheriff’s Office. Chief Deputy Brian Pellerin said Thursday that the investigation hasn’t been completed yet.

Efforts to reach Merrifield on Thursday afternoon were unsuccessful.

District Superintendent Clay Gleason said in an email Friday morning that Merrifield remains on leave as the investigations into the crash, including an internal one conducted by the district, continue.

“I have nothing further I can share at this time but once all the investigations have been completed I’m sure there will be more to share,” Gleason wrote.

Fatal school bus crashes involving Maine children are exceedingly rare: Including Simon and Brayden, only five students have died while getting on or off school buses since 1970, according to the state Department of Transportation.

In response to the two recent deaths, three Democratic state legislators — Reps. Valli Geiger of Rockland and Ann Matlack of St. George and Sen. Pinny Beebe-Center of Knox — say they are authoring a bill to require every Maine school bus to be fitted with a crossing arm, and to require drivers to always use them when dropping off children.

There were an average of 108 school-transportation-related fatalities per year from 2013 to 2022, according to the National Highway Traffic Safety Administration. The NTSB typically investigates 10-12 school bus crashes per year, according to an agency official.

Editor’s note: This story was updated on Jan. 9 to include a statement from the Bonny Eagle school district superintendent.