The deputy stopped the bus carrying eight passengers at 479 Encinitas Blvd. at about 4:25 p.m. and arrested the driver, David Joseph Costello, 40, after conducting a field sobriety test.
Costello is suspected of driving a commercial vehicle while under the influence of alcohol.
A spokesman for NCTD, Alex Wiggins, said the bus was traveling along Route 309, which carries passengers between Oceanside and Encinitas along El Camino Real.
He said First Transit, a company that operates the route under contract with the district, employed the driver.
Wiggins said, "Our focus is 100 percent safety. We want to make sure not just our passengers, but also our employees are safe. Once our investigation is complete we will take whatever appropriate.”
Wiggins said a different driver took over the bus route after the arrest.
"This is a very serious matter and we have advised First Transit that we will be that we operate a safe system. NCTD and conducting an independent investigation, “said NCTD Executive Director Matt Tucker. “NCTD and our contractors view safety as our top priority. A review of our safety record supports our contractors are required by the Federal Transit Administration to maintain a rigorous drug and alcohol testing policy and procedures. These procedures are audited independently by federal and state agencies.”
The driver is being held at the Vista Detention Facility.
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