SALT LAKE CITY — A Utah school bus driver was arrested Monday on suspicion of DUI after driving erratically and nearly hitting a car on a busy stretch of highway while taking 67 elementary-school students on a field trip, authorities said.

Lycia Martinez, 39, is suspected of having taken prescription anti-anxiety/muscle-relaxer pills, which were found in her purse, Utah Highway Patrol Sgt. Blaine Robbins said.

Nobody was hurt on the bus, which had seven adults aboard, and no cars were hit.

“We really dodged a bullet,” Robbins said.