"An ARB investigation showed that MTS failed to meet transit fleet vehicle requirements, and did not inspect their heavy-duty diesel vehicle fleet," according to a statement issued by the state regulatory agency.
Rob Schupp, an MTS spokesman, said the majority of the fines are due to late testing on diesel buses and other vehicles.
"They passed the test, we just missed our deadline," Schupp said.
According to Schupp, only 97 of MTS' 551 vehicles are diesel, and most if not all, will be replaced in the next two years.
"We've got one of the cleanest fleets in the nation," he said.
According to Scripps Ranch residents, for weeks they've been waking up to deep scrapes and scratches that someone keyed in their vehicles, and on Sunday an arrest was made in connection with the incidents.
One person was killed and several others seriously injured in a head-on crash Sunday in Scripps Ranch.
A 71-year-old woman was arrested on suspicion of stabbing her 31-year-old son at least four times with a kitchen knife, when an argument at their San Diego home Sunday escalated into a fight.
The San Diego Gulls will seek their team-record ninth consecutive victory Sunday when they face their rival, the Ontario Reign, at Citizens Business Bank Arena in Ontario.
Some public facilities will be closed Monday in observance of Presidents Day and the Metropolitan Transit System will offer reduced service.
Just the thought of free agent first baseman Eric Hosmer joining the downtrodden, youthful San Diego Padres sent a morning jolt through the spring training clubhouse.
Cold weather, light rain, mountain snow and gusty winds are all in the cards for San Diego County, forecasters said Sunday.