SAN DIEGO (CBS 8) - A union representing some Metropolitan Transit System bus drivers voted on Tuesday night to strike, leaving many MTS Access and mini-bus routes without drivers starting Wednesday.

First Transit had been negotiating with drivers for a few weeks but the two sides were not able to come to an agreement by Tuesday night.

A company called First Transit contracts with MTS to supply drivers for paratransit vehicles and 18 of the agency's bus routes.

RELATED LINK: Service Disruption - MTS Access and some Fixed Routes

Stoppage will begin Wednesday for the MTS Access service and bus routes 14, 18, 25, 83, 84, 88, 833, 851, 870, 944, 945, 946, 964, 965, 972, 973, 978 and 979, according to First Transit.

According to the company, its MTS Access drivers provide 1,900 daily curb-to-curb trips that get people to hospitals, doctor appointments and regional care centers.

The bus routes are generally served by mini-buses and carry around 4,300 passengers a day.

Major bus routes and the trolley would not be affected by a work stoppage.

First Transit had advised passengers to make alternative transportation arrangements in case of a strike.