Law enforcement authorities still don’t know why a Connecticut woman tried to breach a barrier at the White House, setting off a high-speed car chase that put the Capitol on lockdown and ended with her being shot dead by police.

Officials identified the female driver as 34-year-old Miriam Carey, of Stamford, Conn. She was traveling with her 1-year-old daughter who avoided serious injury and was in protective custody late Thursday.

The incident began at about 2:30 p.m. at the White House gates at 15th and E streets NW. Police say Carey had attempted to ram a temporary security barrier outside the White House with her car, then struck a Secret Service uniformed division officer. She then fled the scene, leading police on a chase.

Video submitted to NBC Washington by AlhurraTV shows the woman’s car surrounded by officers with their guns drawn in Garfield Circle, just outside the Capitol. Carey bashes into a barricade, backs up, and then drives away.

Read more: Woman Killed After Police Chase Through Capitol Hill