BUS routes across the west of Scotland are disrupted on Monday as Stagecoach drivers are on strike in a dispute over pay.
The 24-hour walkout, which is affecting services in Ayrshire, Lanarkshire and Glasgow, will be followed by two further strike days on June 2 and 6.
Trade union Unite said six weeks of further action are planned after talks with the bus operator failed to improve on a 4% pay offer for members.
Around 430 drivers operating out of depots in Ayr, Arran, Ardrossan and Kilmarnock are on strike, the union said.
But depots in Dumfries and Galloway are not involved in the action.
Strike action for other days had previously been suspended for further talks after the company withdrew a threat to cancel drivers' annual leave entitlement.
Unite industrial officer, Siobhan McCready, said: "The drivers are being asked to fund a pay rise by working longer hours, taking longer unpaid breaks and losing a week of annual leave."
Stagecoach said several services had been suspended and timetables reduced as it said it wanted a "fair and sustainable" pay deal for drivers that preserves the viability of bus services.
The operator thanked passengers for "patience and understanding" and urged them to check services before setting out to travel.
A Stagecoach spokesperson said: "Regrettably, the industrial action will disrupt our services and inconvenience our customers.
"We're working hard to minimise the impact of this disruption, but unfortunately, the limited services we're running will affect customers travelling in and around Ayrshire."
